Development of a model describing virus removal process in an activated sludge basin

Energy Technology Data Exchange (ETDEWEB)

Kim, T.; Shiragami, N. Unno, H. [Tokyo Institute of Technology, Tokyo (Japan)

1995-06-20

The virus removal process from the liquid phase in an activated sludge basin possibly consists of physicochemical processes, such as adsorption onto sludge flocs, biological processes such as microbial predating and inactivation by virucidal components excreted by microbes. To describe properly the virus behavior in an activated sludge basin, a simple model is proposed based on the experimental data obtained using a poliovirus type 1. A three-compartments model, which include the virus in the liquid phase and in the peripheral and inner regions of sludge flocs is employed. By using the model, the Virus removal process was successfully simulated to highlight the implication of its distribution in the activated sludge basin. 17 refs., 8 figs.

Phase chemistry of tank sludge residual components. 1998 annual progress report

International Nuclear Information System (INIS)

Brady, P.V.; Krumhansl, J.L.; Liu, J.; Nagy, K.L.

1998-01-01

'The proposed research will provide a scientific basis for predicting the long-term fate of radionuclides remaining with the sludge in decommissioned waste tanks. Nuclear activities in the United States and elsewhere produce substantial volumes of highly radioactive semi-liquid slurries that traditionally are stored in large underground tanks while final waste disposal strategies are established. Although most of this waste will eventually be reprocessed a contaminated structure will remain which must either be removed or decommissioned in place. To accrue the substantial savings associated with in-place disposal will require a performance assessment which, in turn, means predicting the leach behavior of the radionuclides associated with the residual sludges. The phase chemistry of these materials is poorly known so a credible source term cannot presently be formulated. Further, handling of actual radioactive sludges is exceedingly cumbersome and expensive. This proposal is directed at: (1) developing synthetic nonradioactive sludges that match wastes produced by the various fuel processing steps, (2) monitoring the changes in phase chemistry of these sludges as they age, and (3) relating the mobility of trace amounts of radionuclides (or surrogates) in the sludge to the phase changes in the aging wastes. This report summarizes work carried out during the first year of a three year project. A prerequisite to performing a meaningful study was to learn in considerable detail about the chemistry of waste streams produced by fuel reprocessing. At Hanford this is not a simple task since over the last five decades four different reprocessing schemes were used: the early BiPO 4 separation for just Pu, the U recovery activity to further treat wastes left by the BiPO 4 activities, the REDOX process and most recently, the PUREX processes. Savannah River fuel reprocessing started later and only PUREX wastes were generated. It is the working premise of this proposal that most

Full-scale performance of selected starch-based biodegradable polymers in sludge dewatering and recommendation for applications.

Science.gov (United States)

Zhou, Kuangxin; Stüber, Johan; Schubert, Rabea-Luisa; Kabbe, Christian; Barjenbruch, Matthias

2018-01-01

Agricultural reuse of dewatered sludge is a valid route for sludge valorization for small and mid-size wastewater treatment plants (WWTPs) due to the direct utilization of nutrients. A more stringent of German fertilizer ordinance requires the degradation of 20% of the synthetic additives like polymeric substance within two years, which came into force on 1 January 2017. This study assessed the use of starch-based polymers for full-scale dewatering of municipal sewage sludge. The laboratory-scale and pilot-scale trials paved the way for full-scale trials at three WWTPs in Germany. The general feasibility of applying starch-based 'green' polymers in full-scale centrifugation was demonstrated. Depending on the sludge type and the process used, the substitution potential was up to 70%. Substitution of 20-30% of the polyacrylamide (PAM)-based polymer was shown to achieve similar total solids (TS) of the dewatered sludge. Optimization of operational parameters as well as machinery set up in WWTPs is recommended in order to improve the shear stability force of sludge flocs and to achieve higher substitution potential. This study suggests that starch-based biodegradable polymers have great potential as alternatives to synthetic polymers in sludge dewatering.

K Basin sludge/resin bead separation test report

International Nuclear Information System (INIS)

Squier, D.M.

1998-01-01

The K Basin sludge is an accumulation of fuel element corrosion products, organic and inorganic ion exchange materials, canister gasket materials, iron and aluminum corrosion products, sand, dirt and minor amounts of other organic material. The sludge will be collected and treated for storage and eventual disposal. This process will remove the large solid materials by a 1/4 inch screen. The screened material will be subjected to nitric acid in a chemical treatment process. The organic ion exchange resin beads produce undesirable chemical reactions with the nitric acid. The resin beads must be removed from the bulk material and treated by another process. An effective bead separation method must extract 95% of the resin bead mass without entraining more than 5% of the other sludge component mass. The test plan I-INF-2729, ''Organic Ion Exchange Resin Separation Methods Evaluation,'' proposed the evaluation of air lift, hydro cyclone, agitated slurry and elutriation resin bead separation methods. This follows the testing strategy outlined in section 4.1 of BNF-2574, ''Testing Strategy to Support the Development of K Basins Sludge Treatment Process''. Engineering study BNF-3128, ''Separation of Organic Ion Exchange Resins from Sludge,'' Rev. 0, focused the evaluation tests on a method that removed the fine sludge particles by a sieve and then extracted the beads by means of a elutriation column. Ninety-nine percent of the resin beads are larger than 125 microns and 98.5 percent are 300 microns and larger. Particles smaller than 125 microns make up the largest portion of sludge in the K Basins. Eliminating a large part of the sludge's non-bead component will reduce the quantity that is lifted with the resin beads in the elutriation column. Resin bead particle size distribution measurements are given in Appendix A The Engineering Testing Laboratory conducted measurements of a elutriation column's ability to extract resin beads from a sieved, non-radioactive sludge

Ferrocyanide Safety Program: Waste tank sludge rheology within a hot spot or during draining

International Nuclear Information System (INIS)

Fauske, H.K.; Cash, R.J.

1993-11-01

The conditions under which ferrocyanide waste sludge flows as a homogeneous non-Newtonian two-phase (solid precipitate-liquid) mixture rather than as a liquid through a porous medium (of stationary precipitate) are examined theoretically, based on the notion that the preferred rheological behavior of the sludge is the one which imposes the least resistance to the sludge flow. The homogeneous two-phase mixture is modeled as a power-law fluid and simple criteria are derived that show that the homogeneous power-law sludge-flow is a much more likely flow situation than the porous medium model of sludge flow. The implication of this finding is that the formation of a hot spot or the drainage of sludge from a waste tank are not likely to result in the uncovering (drying) and subsequent potential overheating of the reactive-solid component of the sludge

The manufacture and use of sludge test materials for R and D purposes in the treatment and processing of magnox based sludge

International Nuclear Information System (INIS)

Blackburn, D.R.; Thompson, E.J.

2013-01-01

Among the Intermediate Level Waste materials in store and awaiting treatment and processing in the UK are quantities of magnesium hydroxide sludge. This sludge is a product of radioactive Magnox Swarf which arose from the de-canning of used magnox fuel element rods. As the Swarf was stored underwater, a corrosion reaction occurred over the course of time between the magnox and the water resulting in a magnesium hydroxide based sludge. The differing conditions and materials present in the various storage areas means that the sludge can range in consistency from that of a slurry through to a thick clay. Sludge test materials are required to underpin and validate the research and development equipment and processes that are to be used to treat the waste material. Necessary restrictions imposed on the sampling and testing of the radioactive waste means that the available data on the properties and behaviour of the sludge is limited. The raw materials used to create the sludge test materials are based upon magnesium hydroxide so that as far as possible the chemical behaviour will be similar to that of the waste material. The most representative sludge test material is manufactured by the corrosion of non-radioactive magnox or magnesium. However, time constraints make it impractical to supply this material in sufficient quantities for full scale validation trials. An alternative is to use sludge manufactured from commercially available magnesium hydroxide. The particle shape of commercially available materials differs from corrosion product magnesium hydroxide which means that properties such as the rheological behaviour cannot be replicated. Nevertheless, valuable trial data can be obtained, giving a greater degree of confidence in the waste treatment process than would be possible if only the more representative but less available corrosion product materials were to be used. Key test material parameters used in the trials have been identified as the particle size

The manufacture and use of sludge test materials for R and D purposes in the treatment and processing of magnox based sludge

Energy Technology Data Exchange (ETDEWEB)

Blackburn, D.R.; Thompson, E.J. [NSG Environmental Ltd, Chorley, Lancashire (United Kingdom)

2013-07-01

Among the Intermediate Level Waste materials in store and awaiting treatment and processing in the UK are quantities of magnesium hydroxide sludge. This sludge is a product of radioactive Magnox Swarf which arose from the de-canning of used magnox fuel element rods. As the Swarf was stored underwater, a corrosion reaction occurred over the course of time between the magnox and the water resulting in a magnesium hydroxide based sludge. The differing conditions and materials present in the various storage areas means that the sludge can range in consistency from that of a slurry through to a thick clay. Sludge test materials are required to underpin and validate the research and development equipment and processes that are to be used to treat the waste material. Necessary restrictions imposed on the sampling and testing of the radioactive waste means that the available data on the properties and behaviour of the sludge is limited. The raw materials used to create the sludge test materials are based upon magnesium hydroxide so that as far as possible the chemical behaviour will be similar to that of the waste material. The most representative sludge test material is manufactured by the corrosion of non-radioactive magnox or magnesium. However, time constraints make it impractical to supply this material in sufficient quantities for full scale validation trials. An alternative is to use sludge manufactured from commercially available magnesium hydroxide. The particle shape of commercially available materials differs from corrosion product magnesium hydroxide which means that properties such as the rheological behaviour cannot be replicated. Nevertheless, valuable trial data can be obtained, giving a greater degree of confidence in the waste treatment process than would be possible if only the more representative but less available corrosion product materials were to be used. Key test material parameters used in the trials have been identified as the particle size

Effects of waste glass additions on quality of textile sludge-based bricks.

Science.gov (United States)

Rahman, Ari; Urabe, Takeo; Kishimoto, Naoyuki; Mizuhara, Shinji

2015-01-01

This research investigated the utilization of textile sludge as a substitute for clay in brick production. The addition of textile sludge to a brick specimen enhanced its pores, thus reducing the quality of the product. However, the addition of waste glass to brick production materials improved the quality of the brick in terms of both compressive strength and water absorption. Maximum compressive strength was observed with the following composition of waste materials: 30% textile sludge, 60% clay and 10% waste glass. The melting of waste glass clogged up pores on the brick, which improved water absorption performance and compressive strength. Moreover, a leaching test on a sludge-based brick to which 10% waste glass did not detect significant heavy metal compounds in leachates, with the product being in conformance with standard regulations. The recycling of textile sludge for brick production, when combined with waste glass additions, may thus be promising in terms of both product quality and environmental aspects.

Phase chemistry and radionuclide retention from simulated tank sludges

International Nuclear Information System (INIS)

KRUMHANSL, JAMES L.; LIU, J.; ARTHUR, SARA E.; HUTCHERSON, SHEILA K.; QIAN, MORRIS; ANDERSON, HOWARD L.

2000-01-01

Decommissioning high level nuclear waste tanks will leave small amounts of residual sludge clinging to the walls and floor of the structures. The permissible amount of material left in the tanks depends on the radionuclide release characteristics of the sludge. At present, no systematic process exists for assessing how much of the remaining inventory will migrate, and which radioisotopes will remain relatively fixed. Working with actual sludges is both dangerous and prohibitively expensive. Consequently, methods were developed for preparing sludge simulants and doping them with nonradioactive surrogates for several radionuclides and RCRA metals of concern in actual sludges. The phase chemistry of these mixes was found to be a reasonable match for the main phases in actual sludges. Preliminary surrogate release characteristics for these sludges were assessed by lowering the ionic strength and pH of the sludges in the manner that would occur if normal groundwater gained access to a decommissioned tank. Most of the Se, Cs and Tc in the sludges will be released into the first pulse of groundwater passing through the sludge. A significant fraction of the other surrogates will be retained indefinitely by the sludges. This prolonged sequestration results from a combination coprecipitated and sorbed into or onto relatively insoluble phases such as apatite, hydrous oxides of Fe, Al, Bi and rare earth oxides and phosphates. The coprecipitated fraction cannot be released until the host phase dissolves or recrystallizes. The sorbed fraction can be released by ion exchange processes as the pore fluid chemistry changes. However, these releases can be predicted based on a knowledge of the fluid composition and the surface chemistry of the solids. In this regard, the behavior of the hydrous iron oxide component of most sludges will probably play a dominant role for many cationic radionuclides while the hydrous aluminum oxides may be more important in governing anion releases

Sludge derived fuel technique of sewage sludge by oil vacuum evaporation drying

International Nuclear Information System (INIS)

Kim, Seokhwan; Lim, Byungran; Lee, Sookoo

2010-01-01

Sewage sludge contains high content of organic materials and its water content is also very high about 80% even after filtration process. Landfill as a sludge treatment methods can cause odor problem and leachate production which can derive the secondary contamination of soil and groundwater. The ocean dumping will be prohibited according to the London Convention and domestic stringent environmental regulation. Based on domestic agenda on organic sewage sludge treatment, the ocean disposal will be prohibited from 2012, thus alternative methods are demanded. Sludge derived fuel (SDF) technology can alleviate the emission of greenhouse gas and recover energy from sludge. For proper treatment and SDF production from sludge, the vacuum evaporation and immersion frying technology was adopted in this research. This technology dries moisture in sludge after mixing with oil such as Bunker C oil, waste oil or waste food oil etc. Mixing sludge and oil secures liquidity of organic sludge to facilitate handling throughout the drying process. The boiling temperature could be maintained low through vacuum condition in whole evaporation process. This study was performed to find the optimum operating temperature and pressure, the mixing ratio of sludge and oil. Finally, we could obtained SDF which moisture content was less than 5%, its heating value was over 4,500 kcal/ kg sludge. This heating value could satisfy the Korean Fuel Standard for the Recycle Products. Assessed from the perspective of energy balance and economic evaluation, this sludge drying system could be widely used for the effective sludge treatment and the production of SDF. (author)

EFFECTIVENESS OF USING DILUTE OXALIC ACID TO DISSOLVE HIGH LEVEL WASTE IRON BASED SLUDGE SIMULANT

International Nuclear Information System (INIS)

Ketusky, E

2008-01-01

At the Savannah River Site (SRS), near Aiken South Carolina, there is a crucial need to remove residual quantities of highly radioactive iron-based sludge from large select underground storage tanks (e.g., 19,000 liters of sludge per tank), in order to support tank closure. The use of oxalic acid is planned to dissolve the residual sludge, hence, helping in the removal. Based on rigorous testing, primarily using 4 and 8 wt% oxalic acid solutions, it was concluded that the more concentrated the acid, the greater the amount of residual sludge that would be dissolved; hence, a baseline technology on using 8 wt% oxalic acid was developed. In stark contrast to the baseline technology, reports from other industries suggest that the dissolution will most effectively occur at 1 wt% oxalic acid (i.e., maintaining the pH near 2). The driver for using less oxalic acid is that less (i.e., moles) would decrease the severity of the downstream impacts (i.e., required oxalate solids removal efforts). To determine the initial feasibility of using 1 wt% acid to dissolve > 90% of the sludge solids, about 19,000 liters of representative sludge was modeled using about 530,000 liters of 0 to 8 wt% oxalic acid solutions. With the chemical thermodynamic equilibrium based software results showing that 1 wt% oxalic acid could theoretically work, simulant dissolution testing was initiated. For the dissolution testing, existing simulant was obtained, and an approximate 20 liter test rig was built. Multiple batch dissolutions of both wet and air-dried simulant were performed. Overall, the testing showed that dilute oxalic acid dissolved a greater fraction of the stimulant and resulted in a significantly larger acid effectiveness (i.e., grams of sludge dissolved/mole of acid) than the baseline technology. With the potential effectiveness confirmed via simulant testing, additional testing, including radioactive sludge testing, is planned

Sewage sludge as a biomass energy source

Directory of Open Access Journals (Sweden)

Pavel Kolat

2013-01-01

Full Text Available The major part of the dry matter content of sewage sludge consists of nontoxic organic compounds, in general a combination of primary sludge and secondary microbiological sludge. The sludge also contains a substantive amount of inorganic material and a small amount of toxic components. There are many sludge-management options in which production of energy is one of the key treatment steps. The most important options are anaerobic digestion, co-digestion, incineration in combination with energy recovery and co-incineration in coal-fired power plants. The goal of our applied research is to verify, if the sludge from waste water treatment plants may be used as a biomass energy source in respect of the EU legislation, which would comply with emission limits or the proposal of energy process optimizing the preparation of coal/sludge mixture for combustion in the existing fluid bed boilers in the Czech Republic. The paper discusses the questions of thermal usage of mechanically drained stabilized sewage sludge from the waste water treatment plants in the boiler with circulated fluid layer. The paper describes methods of thermal analysis of coal, sewage sludge and its mixtures, mud transport to the circulating fluidised bed boiler, effects on efficiency, operational reliability of the combustion equipment, emissions and solid combustion residues.

REDUCTION OF EXCESS SLUDGE PRODUCTION IN AN ACTIVATED SLUDGE SYSTEM BASED ON LYSIS-CRYPTIC GROWTH, UNCOUPLING METABOLISM AND FOLIC ACID ADDITION

Directory of Open Access Journals (Sweden)

V. F. Velho

Full Text Available Abstract The following sludge reduction alternatives were tested in wastewater biological reactors: oxic-settling-anaerobic (OSA-process; ultrasonic disintegration (UD; chlorination (CH; 3,3',4',5-tetrachlorosalicylanilide (TCS; and folic acid (FA. Compared to the control system, UD reduced 55% of the sludge production, and greater substrate and nutrient removal efficiency was achieved. CH worsened the sludge settleability and increased the SVI values; the system achieved 25% of sludge reduction. OSA showed 50% and 60% of sludge reduction after 16 and 10 hours under anaerobic conditions, respectively. The observed sludge yield during TCS addition was decreased by 40%, and the sludge settleability worsened. FA presented the highest sludge reduction (75%, and the system improved the nutrient removal efficiency by 30% compared to the control system and maintained the sludge properties. Acute toxicity conducted with Daphnia magna classified the effluent from the sludge reduction systems as non-toxic for discharge into water sources.

Analysis of petroleum oily sludge producing in petroleum field of Rio Grande do Norte, Brazil

Energy Technology Data Exchange (ETDEWEB)

Lima, Cicero de Souza; Lima, Regineide Oliveira; Silva, Edjane Fabiula Buriti da; Castro, Kesia Kelly Vieira de; Chiavone Filho, Osvaldo; Araujo, Antonio Souza de [Universidade Federal do Rio Grande do Norte (UFRN), RN (Brazil)

2012-07-01

In exploration and production of petroleum is generated solid waste different and components other. The petroleum oily sludge is a complex mix of components different (water, oil and solid). The petroleum oily sludge generally has other residues and is formed during production and operations, transport, storage and petroleum refining (atmospheric residue, vacuum residue and catalytic cracking residue). However, according to its origin, the compositions can be found quite varied for sludge. Observing the process steps production and refining is possible to locate its main sources and percentage contributions in terms of waste generation. The elemental analysis was performed with oily sludge from region and it showed different composition. For carbon element and hydrogen, small differences was observed, but for was observed greater differences for Oxygen element. The sludge has different inorganic and organic composition. The sludge from oil water separator (OWS) 2 showed a greater amount of oil (94.88%), this may indicate a residue of aggregate high for petroleum industry. In analysis of Saturates, Aromatics, Resins and Asphaltenes (SARA), the sludge from unloading showed amount high of saturates. The inorganic material separated from sludge was characterized and sludge from OWS 2 had high amount sulfur (41.57%). The sludge analyzed showed organic components high values, so it can be treated and reprocessed in process units petroleum industry. The analysis thermal degradation had a better setting for treated oily sludge. (author)

Sustainable sludge management in developing countries

Energy Technology Data Exchange (ETDEWEB)

Jimenez, B.; Barrios, J.A.; Mendez, J.M.; Diaz, J.

2003-07-01

Worldwide, unsanitary conditions are responsible of more than three million deaths annually. One of the reasons is the low level of sanitation in developing countries. Particularly, sludge from these regions has a high parasite concentration and low heavy metal content even though the available information is limited. Different issues needed to achieve a sustainable sludge management in developing nations are analysed. Based on this analysis some conclusions arise: sludge management plays an important role in sanitation programs by helping reduce health problems and associated risks; investments in sanitation should consider sludge management within the overall projects; the main restriction for reusing sludge is the high microbial concentration, which requires a science-based decision of the treatment process, while heavy metals are generally low; the adequate sludge management needs the commitment of those sectors involved in the development and enforcement of the regulations as well as those that are directly related to its generation, treatment, reuse or disposal; current regulations have followed different approaches, based mainly on local conditions, but they favour sludge reuse to fight problems like soil degradation, reduced crop production, and the increased use of inorganic fertilizers. This paper summarises an overview of theses issues. (author)

Caustic leaching of composite AZ-101/AZ-102 Hanford tank sludge

International Nuclear Information System (INIS)

Rapko, B.M.; Wagner, M.J.

1997-07-01

To reduce the quantity (and hence the cost) of glass canisters needed for disposing of high-level radioactive wastes from the Hanford tank farms, pretreatment processes are needed to remove as much nonradioactive material as possible. This report describes the results of a laboratory-scale caustic leaching test performed on a composite derived from a combination of 241-AZ-101 and 241-AZ-102 Hanford Tank sludges. The goals of this FY 1996 test were to evaluate the effectiveness of caustic leaching on removing key components from the sludge and to evaluate the effectiveness of varying the free-hydroxide concentrations by incrementally increasing the free hydroxide concentration of the leach steps up to 3 M free hydroxide. Particle-size analysis of the treated and untreated sludge indicated that the size and range of the sludge particles remained essentially unchanged by the caustic leaching treatment. Both before and after caustic leaching, a particle range of 0.2 microm to 50 microm was observed, with mean particle diameters of 8.5 to 9 microm based on the volume distribution and mean particle diameters of 0.3 to 0.4 microm based on the number distribution

Status Report on Phase Identification in Hanford Tank Sludges

International Nuclear Information System (INIS)

Rapko, B.M.; Lumetta, G.J.

2000-01-01

The US Department of Energy plans to vitrify Hanford's tank wastes. The vitrified wastes will be divided into low-activity and high-level fractions. There is an effort to reduce the quantity of high-activity wastes by removing nonradioactive components because of the high costs involved in treating high-level waste. Pretreatment options, such as caustic leaching, to selectively remove nonradioactive components are being investigated. The effectiveness of these proposed processes for removing nonradioactive components depends on the chemical phases in the tank sludges. This review summarizes the chemical phases identified to date in Hanford tank sludges

Reconfirmation of frit 803 based on the January 2016 sludge batch 9 reprojection

Energy Technology Data Exchange (ETDEWEB)

Johnson, F. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Edwards, T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2016-02-10

On January 11, 2016, Savannah River Remediation (SRR) provided the Savannah River National Laboratory (SRNL) with a Sludge Batch 9 (SB9) reprojection that was developed from the analyzed composition of a Tank 51 sample. This sample was collected after field washing had been completed in Tank 51 to support the alternate reductant task. Based on this reprojection, Frit 803 is still a viable option for the processing of SB9 under sludge-only operations and coupled (Actinide Removal Process (ARP) product with and without monosodium titanate (MST)) operations. The maximum projected volumes of ARP product that can be transferred from the Precipitate Reactor Feed Tank (PRFT) per Sludge Receipt and Adjustment Tank (SRAT) batch and the resulting Na₂O concentrations in the SRAT for coupled operations were determined. The Na₂O concentrations in the SRAT resulting from the maximum projected ARP product transfer volumes are consistent with those from the previous assessments that were based on the August 2015 projections. Regardless of the presence or absence of MST in the ARP product, the contribution of Na₂O to the resulting glass will be similar at the same waste loading (WL). These projected volumes of ARP product are not anticipated to be an issue for SB9. The actual transfer volumes from the PRFT to the SRAT are determined based upon the analyzed Na₂O concentrations in the PRFT samples, which has resulted in larger transfer volumes than those allowed by the projections for Sludge Batch 8 (SB8). An operating window of 32-40% WL around the nominal WL of 36% is achievable for both sludge-only and coupled operations; however, each of the glass systems studied does become limited by waste form affecting constraints (durability) at higher volumes of ARP product and WLs of 41-42%.

Pentachlorophenol (PCP) sludge recycling unit

International Nuclear Information System (INIS)

1994-08-01

The Guelph Utility Pole Company treats utility poles by immersion in pentachlorophenol (PCP) or by pressure treatment with chromated copper arsenate (CCA). The PCP treatment process involves a number of steps, each producing a certain amount of sludge and other wastes. In a plant upgrading program to improve processing and treatment of poles and to reduce and recycle waste, a PCP recovery unit was developed, first as an experimental pilot-scale unit and then as a full-scale unit. The PCP recovery unit is modular in design and can be modified to suit different requirements. In a recycling operation, the sludge is pumped through a preheat system (preheated by waste heat) and suspended solids are removed by a strainer. The sludge is then heated in a tank and at a predetermined temperature it begins to separate into its component parts: oil, steam, and solids. The steam condenses to water containing low amounts of light oil, and this water is pumped through an oil/water separator. The recovered oil is reused in the wood treatment process and the water is used in the CCA plant. The oil remaining in the tank is reused in PCP treatment and the solid waste, which includes small stones and wood particles, is removed and stored. By the third quarter of operation, the recovery unit was operating as designed, processing ca 10,000 gal of sludge. This sludge yielded 6,500 gal of water, 3,500 gal of oil, and ca 30 gal of solids. Introduction of the PCP sludge recycling system has eliminated long-term storage of PCP sludge and minimized costs of hazardous waste disposal. 4 figs

Evaluation of a microwave based reactor for the treatment of blackwater sludge

Energy Technology Data Exchange (ETDEWEB)

Mawioo, Peter M., E-mail: p.mawioo@unesco-ihe.org [Department of Environmental Engineering and Water Technology, UNESCO-IHE Institute for Water Education, Westvest 7, 2611 AX Delft (Netherlands); Rweyemamu, Audax; Garcia, Hector A.; Hooijmans, Christine M. [Department of Environmental Engineering and Water Technology, UNESCO-IHE Institute for Water Education, Westvest 7, 2611 AX Delft (Netherlands); Brdjanovic, Damir [Department of Environmental Engineering and Water Technology, UNESCO-IHE Institute for Water Education, Westvest 7, 2611 AX Delft (Netherlands); Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft (Netherlands)

2016-04-01

A laboratory-scale microwave (MW) unit was applied to treat fresh blackwater sludge that represented fecal sludge (FS) produced at heavily used toilet facilities. The sludge was exposed to MW irradiation at different power levels and for various durations. Variables such as sludge volume and pathogen reduction were observed. The results demonstrated that the MW is a rapid and efficient technology that can reduce the sludge volume by over 70% in these experimental conditions. The concentration of bacterial pathogenic indicator E. coli also decreased to below the analytical detection levels. Furthermore, the results indicated that the MW operational conditions including radiation power and contact time can be varied to achieve the desired sludge volume and pathogen reduction. MW technology can be further explored for the potential scaling-up as an option for rapid treatment of FS from intensively used sanitation facilities such as in emergency situations. - Highlights: • There is lack of fast and efficient fecal sludge treatment options in emergencies. • Microwave treatment is rapid and efficient in sludge volume and pathogen reduction. • Power and contact time can be varied to reach diverse levels of sludge treatment.

Evaluation of a microwave based reactor for the treatment of blackwater sludge

International Nuclear Information System (INIS)

Mawioo, Peter M.; Rweyemamu, Audax; Garcia, Hector A.; Hooijmans, Christine M.; Brdjanovic, Damir

2016-01-01

A laboratory-scale microwave (MW) unit was applied to treat fresh blackwater sludge that represented fecal sludge (FS) produced at heavily used toilet facilities. The sludge was exposed to MW irradiation at different power levels and for various durations. Variables such as sludge volume and pathogen reduction were observed. The results demonstrated that the MW is a rapid and efficient technology that can reduce the sludge volume by over 70% in these experimental conditions. The concentration of bacterial pathogenic indicator E. coli also decreased to below the analytical detection levels. Furthermore, the results indicated that the MW operational conditions including radiation power and contact time can be varied to achieve the desired sludge volume and pathogen reduction. MW technology can be further explored for the potential scaling-up as an option for rapid treatment of FS from intensively used sanitation facilities such as in emergency situations. - Highlights: • There is lack of fast and efficient fecal sludge treatment options in emergencies. • Microwave treatment is rapid and efficient in sludge volume and pathogen reduction. • Power and contact time can be varied to reach diverse levels of sludge treatment.

Copper stabilization in beneficial use of waterworks sludge and copper-laden electroplating sludge for ceramic materials.

Science.gov (United States)

Tang, Yuanyuan; Chan, Siu-Wai; Shih, Kaimin

2014-06-01

A promising strategy for effectively incorporating metal-containing waste materials into a variety of ceramic products was devised in this study. Elemental analysis confirmed that copper was the predominant metal component in the collected electroplating sludge, and aluminum was the predominant constituent of waterworks sludge collected in Hong Kong. The use of waterworks sludge as an aluminum-rich precursor material to facilitate copper stabilization under thermal conditions provides a promising waste-to-resource strategy. When sintering the mixture of copper sludge and the 900 °C calcined waterworks sludge, the CuAl2O4 spinel phase was first detected at 650 °C and became the predominant product phase at temperatures higher than 850 °C. Quantification of the XRD pattern using the Rietveld refinement method revealed that the weight of the CuAl2O4 spinel phase reached over 50% at 850 °C. The strong signals of the CuAl2O4 phase continued until the temperature reached 1150 °C, and further sintering initiated the generation of the other copper-hosting phases (CuAlO2, Cu2O, and CuO). The copper stabilization effect was evaluated by the copper leachability of the CuAl2O4 and CuO via the prolonged leaching experiments at a pH value of 4.9. The leaching results showed that the CuAl2O4 phase was superior to the CuAlO2 and CuO phases for immobilizing hazardous copper over longer leaching periods. The findings clearly indicate that spinel formation is the most crucial metal stabilization mechanism when sintering multiphase copper sludge with aluminum-rich waterworks sludge, and suggest a promising and reliable technique for reusing both types of sludge waste for ceramic materials. Copyright © 2013 Elsevier Ltd. All rights reserved.

Co-conditioning and dewatering of chemical sludge and waste activated sludge.

Science.gov (United States)

Chang, G R; Liu, J C; Lee, D J

2001-03-01

The conditioning and dewatering behaviors of chemical and waste activated sludges from a tannery were studied. Capillary suction time (CST), specific resistance to filtration (SRF), and bound water content were used to evaluate the sludge dewatering behaviors. Zeta potentials were also measured. Experiments were conducted on each sludge conditioned and dewatered separately, and on the sludge mixed at various ratios. Results indicate that the chemical sludge was relatively difficult to be dewatered, even in the presence of polyelectrolyte. When the waste activated sludge was mixed with the chemical sludge at ratios of 1:1 and 2:1, respectively, the dewaterability of chemical sludge improved remarkably while the relatively better dewaterability of the waste activated sludge deteriorated only to a limited extent. As the mixing ratios became 4:1 and 8:1, the dewaterability of the mixed sludge was equal to that of the waste activated sludge. The optimal polyelectrolyte dosage for the mixed sludge was equal to or less than that of the waste activated sludge. It is proposed that the chemical sludges act as skeleton builders that reduce the compressibility of the mixed sludge whose dewaterability is enhanced. Bound water contents of sludge decreased at low polyelectrolyte dosage and were not significantly affected as polyelectrolyte dosage increased. Advantages and disadvantages of co-conditioning and dewatering chemical sludge and waste activated sludge were discussed.

Removal of lead (II) from metal plating effluents using sludge based activated carbon as adsorbent.

Science.gov (United States)

Raju, P; Saseetharan, M K

2010-01-01

A novel adsorbent was prepared from waste sludge obtained from a sugar mill for removing heavy metals from industrial wastewater. The adsorption studies were carried out in batch and continuous modes for both sugar mill sludge based carbon and commercial carbon. In batch studies, experiments were conducted at ambient temperature to assess the influence of the parameters such as pH, adsorbent dose, contact time and equilibrium concentration. Adsorption data for the prepared carbon was found to satisfy both the Freundlich and Langmuir isotherms. Column studies were carried out to delineate the effect of varying depth of carbon at constant flow rate. The breakthrough curves were drawn to establish the mechanism. The result shows that the sludge based activated carbon can be used as an alternative for commercial carbon.

Minimization of Excess Sludge in Activated Sludge Systems

Directory of Open Access Journals (Sweden)

Sayed Ali Reza Momeni

2006-01-01

Full Text Available The disposal of excess sludge from wastewater treatment plant represents a rising challenge in activated sludge processes. Hence, the minimization of excess sludge production was investigated by increasing the dissolved oxygen in aeration basin. Units of the pilot include: Primary sedimentation tank, aeration basin, secondary sedimentation tank, and return sludge tank. Volume of aeration basin is 360 l and influent flow rate is 90 L/h. Influent of pilot is taken from effluent of grit chamber of Isfahan's North Wastewater treatment plant. The experiments were done on different parts of pilot during the 5 month of study. Results show that increase of dissolved oxygen in aeration tank affect on decrease of excess sludge. Increase of dissolved oxygen from 0.5 to 4.5 mg/L resulted in 25% decrease of excess sludge. Variation of dissolved oxygen affect on settleability of sludge too. By increase of dissolved oxygen, SVI decreased and then increased. Value of 1-3 mg/L was the adequate range of dissolved oxygen by settleability of sludge and optimum range was 2-2.5 mg/L. It could be concluded by increasing of dissolved oxygen up to of 3 mg/L, sludge settleability significant decreased.

Selective hydrolysis of wastewater sludge. Part 1. Model calculations and cost benefit analysis for Esbjerg West waste water treatment plant, Denmark

Energy Technology Data Exchange (ETDEWEB)

OEstergaard, N [Eurotec West A/S (DK); Thomsen, Anne Belinda; Thygesen, Anders; Bangsoe Nielsen, H [Risoe National Laboratory, DTU (DK); Rasmussen, Soeren [SamRas (DK)

2007-09-15

The project 'Selective hydrolysis of wastewater sludge' investigates the possibilities of utilizing selective hydrolysis of sludge at waste water treatment plants to increase the production of biogas based power and heat, and at the same time reduce power consumption for handling and treatment of nitrogen and sludge as well as for disposal of the sludge. The selective hydrolysis system is based on the fact that an anaerobic digestion before a hydrolysis treatment increases the hydrolysis efficiency, as the production of volatile organic components, which might inhibit the hydrolysis efficiency, are not produced to the same extent as may be the case for a hydrolysis made on un-digested material. Furthermore it is possible to separate ammonia from the sludge without using chemicals; it has, however, proven difficult to treat wastewater sludge, as the sludge seems to be difficult to treat in the laboratory using simple equipment. Esbjerg Wastewater Treatment Plant West, Denmark, is used as model plant for the calculations of the benefits using selective hydrolysis of sludge as if established at the existing sludge digester system. The plant is a traditional build plant based on the activated sludge concept in addition to traditional digester technology. The plant treats combined household and factory wastewater with a considerable amount of the wastewater received from the industries. During the project period Esbjerg Treatment Plant West went through considerable process changes, thus the results presented in this report are based on historical plant characteristics and may be viewed as conservative relative to what actually may be obtainable. (BA)

Selective hydrolysis of wastewater sludge. Part 1. Model calculations and cost benefit analysis for Esbjerg West waste water treatment plant, Denmark

Energy Technology Data Exchange (ETDEWEB)

OEstergaard, N. (Eurotec West A/S (DK)); Thomsen, Anne Belinda; Thygesen, Anders; Bangsoe Nielsen, H. (Risoe National Laboratory, DTU (DK)); Rasmussen, Soeren (SamRas (DK))

2007-09-15

The project 'Selective hydrolysis of wastewater sludge' investigates the possibilities of utilizing selective hydrolysis of sludge at waste water treatment plants to increase the production of biogas based power and heat, and at the same time reduce power consumption for handling and treatment of nitrogen and sludge as well as for disposal of the sludge. The selective hydrolysis system is based on the fact that an anaerobic digestion before a hydrolysis treatment increases the hydrolysis efficiency, as the production of volatile organic components, which might inhibit the hydrolysis efficiency, are not produced to the same extent as may be the case for a hydrolysis made on un-digested material. Furthermore it is possible to separate ammonia from the sludge without using chemicals; it has, however, proven difficult to treat wastewater sludge, as the sludge seems to be difficult to treat in the laboratory using simple equipment. Esbjerg Wastewater Treatment Plant West, Denmark, is used as model plant for the calculations of the benefits using selective hydrolysis of sludge as if established at the existing sludge digester system. The plant is a traditional build plant based on the activated sludge concept in addition to traditional digester technology. The plant treats combined household and factory wastewater with a considerable amount of the wastewater received from the industries. During the project period Esbjerg Treatment Plant West went through considerable process changes, thus the results presented in this report are based on historical plant characteristics and may be viewed as conservative relative to what actually may be obtainable. (BA)

Sewage sludge used as organic manure in Moroccan sunflower culture: Effects on certain soil properties, growth and yield components.

Science.gov (United States)

Mohamed, Bourioug; Mounia, Krouna; Aziz, Abouabdillah; Ahmed, Harraq; Rachid, Bouabid; Lotfi, Aleya

2018-06-15

The wastewater treatment and sludge production sectors in Morocco are recent. Considered as waste, no management strategy for sewage sludge (SS) has been implemented. Thus, its disposal definitely represents a major environmental problem since sludge is either incinerated, used as landfill or simply deposited near wastewater treatment plants. The objective of this study was to determine the effects of dehydrated SS on certain soil properties (pH, electrical conductivity (EC), Mineral nitrogen, available phosphate P 2 O 5 , and soluble potassium K 2 O), and also on growth and yield components of the sunflower (Helianthus annuus L.). An experiment was conducted using six treatment rates (0; 0 + NPK; 15; 30; 60 and 120 t ha -1 ). The results showed that soil pH was significantly affected by SS, becoming less alkaline compared to the control, while electrical conductivity increased significantly when the applied doses were above 30 t ha -1 . Also, a significant enrichment in mineral N and available phosphorus was detected in amended soil. However, no differences were found between pots having received the mineral fertilization and the SS at 15 t ha -1 . Stem height growth of the sunflower seedlings receiving SS increased significantly compared to the two controls. For both the aerial and root parts, significant increases in dry biomass accumulation were observed compared to the unamended plants. Net CO 2 assimilation (A n ) increased, while stomatal conductance (g sw ) and transpiration rates (T r ) decreased with increasing SS rates. SS application at 15 t ha -1 presented similar values of the yield components compared to plants fertilized chemically. However, grain yield (in quintals ha -1 ) was noted to be 2.4, 5 and 8 times higher in treatments receiving SS respectively at the rate of 30, 60 and 120 t ha -1 . Copyright © 2018 Elsevier B.V. All rights reserved.

Operational strategy, economic and environmental performance of sludge treatment reed bed systems - based on 28 years of experience

DEFF Research Database (Denmark)

Nielsen, S.; Larsen, Julie Dam

2016-01-01

Sludge treatment reed bed (STRB) systems have been used for dewatering and mineralisation of sludge in Europe since 1988. STRB systems provide substantial environmental, economic, and operational benefits compared to mechanical sludge dewatering solutions such as belt presses and centrifuges....... They require less energy, no chemicals, reduce the sludge volume and produce bio solids with dry solid contents up to 20-40% under Danish climate conditions, depending on the sludge quality. Experience has shown that sludge treated in STRBs represents a high quality product with a low content of pathogens...... compared to conventional mechanical dewatering devices, delivering an economic break-even of about 3-5 years. This paper provides an overview of the operation and maintenance costs and environmental benefits of a typical STRB based on the experiences gained from the operation of a large number of STRBs...

Inhibition of total oxygen uptake by silica nanoparticles in activated sludge

Energy Technology Data Exchange (ETDEWEB)

Sibag, Mark [Department of Environment and Energy, Sejong University, 98 Gunja-Dong, Gwangjin-Gu, Seoul 143-747 (Korea, Republic of); Choi, Byeong-Gyu [School of Civil, Environmental and Architectural Engineering, Korea University, 145, Anam-ro, Sungbuk-ku, Seoul 136-701 (Korea, Republic of); Suh, Changwon [Energy Lab, Environment Group, Samsung Advanced Institute of Technology, 130 Samsung-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do 443-803 (Korea, Republic of); Lee, Kwan Hyung; Lee, Jae Woo [Department of Environmental Engineering and Program in Environmental Technology and Policy, Korea University, Sejong 339-700 (Korea, Republic of); Maeng, Sung Kyu [Department of Civil and Environmental Engineering, Sejong University, 98 Gunja-Dong, Gwangjin-Gu, Seoul 143-747 (Korea, Republic of); Cho, Jinwoo, E-mail: jinwoocho@sejong.edu [Department of Environment and Energy, Sejong University, 98 Gunja-Dong, Gwangjin-Gu, Seoul 143-747 (Korea, Republic of)

2015-02-11

Highlights: • Silica nanoparticles (SNP) inhibit total oxygen uptake in activated sludge. • Relatively smaller SNP are inhibitorier than larger SNP. • SNP alters C15:0, C16:0 and C18:0 in activated sludge fatty acid methyl ester profile. - Abstract: Nanoparticle toxicity to biological activities in activated sludge is largely unknown. Among the widely used nanoparticles, silica nanoparticles (SNP) have a limited number of studies associated with inhibition to the activated sludge process (ASP). We demonstrated SNP inhibition of activated sludge respiration through oxygen uptake rate (OUR) measurement. Based on the percentage inhibition of total oxygen consumption (I{sub T}), we observed that smaller SNPs (12 nm, I{sub T} = 33 ± 3%; 151 nm, I{sub T} = 23 ± 2%) were stronger inhibitors than larger SNPs (442 and 683 nm, I{sub T} = 5 ± 1%). Transmission electron micrographs showed that some of the SNPs were adsorbed on and/or apparently embedded somewhere in the microbial cell membrane. Whether SNPs are directly associated with the inhibition of total oxygen uptake warrants further studies. However, it is clear that SNPs statistically significantly altered the composition of microbial membrane lipids, which was more clearly described by principal component analysis and weighted Euclidian distance (PCA-ED) of the fatty acid methyl ester (FAME) data. This study suggests that SNPs potentially affect the biological activity in activated sludge through the inhibition of total oxygen uptake.

Lipid profiling in sewage sludge.

Science.gov (United States)

Zhu, Fenfen; Wu, Xuemin; Zhao, Luyao; Liu, Xiaohui; Qi, Juanjuan; Wang, Xueying; Wang, Jiawei

2017-06-01

High value-added reutilization of sewage sludge from wastewater treatment plants (WWTPs) is essential in sustainable development in WWTPs. However, despite the advantage of high value reutilization, this process must be based on a detailed study of organics in sludge. We used the methods employed in life sciences to determine the profile of lipids (cellular lipids, free fatty acids (FFAs), and wax/gum) in five sludge samples obtained from three typical WWTPs in Beijing; these samples include one sludge sample from a primary sedimentation tank, two activated sludge samples from two Anaerobic-Anoxic-Oxic (A2/O) tanks, and two activated sludge samples from two membrane bioreactor tanks. The percentage of total raw lipids varied from 2.90% to 12.3%. Sludge from the primary sedimentation tank showed the highest concentrations of lipid, FFA, and wax/gum and the second highest concentration of cellular lipids. All activated sludge contained an abundance of cellular lipids (>54%). Cells in sludge can from plants, animals, microbes and so on in wastewater. Approximately 14 species of cellular lipids were identified, including considerable high value-potential ceramide (9567-38774 mg/kg), coenzyme (937-3897 mg/kg), and some phosphatidylcholine (75-548 mg/kg). The presence of those lipid constituents would thus require a wider range of recovery methods for sludge. Both cellular lipids and FFAs contain an abundance of C16-C18 lipids at high saturation level, and they serve as good resources for biodiesel production. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ultrasonic reduction of excess sludge from the activated sludge system

International Nuclear Information System (INIS)

Zhang Guangming; Zhang Panyue; Yang Jinmei; Chen Yanming

2007-01-01

Sludge treatment has long become the most challenging problem in wastewater treatment plants. Previous studies showed that ozone or chlorine effectively liquefies sludge into substrates for bio-degradation in the aeration tank, and thus reduces the excess sludge. This paper employs ultrasound to reduce the excess sludge from the sequential batch reactor (SBR) system. Partial sludge was disintegrated into dissolved substrates by ultrasound in an external sono-tank and was then returned to the SBR for bio-degradation. The results showed that ultrasound (25 kHz) effectively liquefied the sludge. The most effective conditions for sludge reduction were as following: sludge sonication ratio of 3/14, ultrasound intensity of 120 kW/kgDS, and sonication duration of 15 min. The amount of excess sludge was reduced by 91.1% to 17.8 mg/(L d); the organic content and settleability of sludge in the SBR were not impacted. The chemical oxygen demand (COD) removal efficiency was 81.1%, the total nitrogen (TN) removal efficiency was 17-66%, and high phosphorus concentration in the effluent was observed

Physical property characterization of 183-H Basin sludge

International Nuclear Information System (INIS)

Biyani, R.K.; Delegard, C.H.

1995-01-01

This document describes the characterization of 183-H Basin sludge physical properties, e.g. bulk density of sludge and absorbent, and determination of free liquids. Calcination of crucible-size samples of sludge was also done and the resulting 'loss-on-ignition' was compared to the theoretical weight loss based on sludge analysis obtained from Weston Labs

Biosorption of chromium, copper and zinc by wine-processing waste sludge: Single and multi-component system study

International Nuclear Information System (INIS)

Liu, Cheng-Chung; Wang, Ming-Kuang; Chiou, Chyow-San; Li, Yuan-Shen; Yang, Chia-Yi; Lin, Yu-An

2009-01-01

Wine-processing waste sludge (WPWS) has been shown to have powerful potential for sorption of some heavy metals (i.e., chromium, lead and nickel) in single-component aqueous solutions. But although most industrial wastewater contains two or more toxic metals, there are few sorption studies on multicomponent metals by WPWS. This study has two goals: (i) conduct competitive adsorption using Cr, Cu and Zn as sorbates and examine their interaction in binary or ternary systems; and (ii) determine the effects of temperature on the kinetic sorption reaction. The sludge tested contained a high amount of organic matter (38%) and had a high cation exchange capacity (CEC, 255 cmol c kg -1 ). Infrared analysis reveals that carboxyl is the main functional group in this WPWS. The 13 C NMR determination indicates alkyl-C and carboxyl-C are major organic functional groups. At steady state, there are about 40.4% (Cr), 35.0% (Cu) and 21.9% (Zn) sorbed in the initial 6.12 mM of single-component solutions. Only pseudo-second-order sorption kinetic model successfully describes the kinetics of sorption for all experimental metals. The rate constants, k 2 , of Cr, Cu and Zn in single-component solutions are 0.016, 0.030 and 0.154 g mg -1 min -1 , respectively. The sorption of metals by WPWS in this competitive system shows the trend: Cr > Cu > Zn. Ions of charge, hydrated radius and electronic configuration are main factors affecting sorption capacity. The least sorption for Zn in this competitive system can be attributed to its full orbital and largest hydrated radius. Though the effect of temperature on Zn sorption is insignificant, high temperature favors the other metallic sorptions, in particular for Cr. However, the Cr sorption is lower than Cu at 10 deg. C. The Cr sorption by WPWS can be higher than that of Cu at 30 deg. and 50 deg. C.

Biosorption of chromium, copper and zinc by wine-processing waste sludge: Single and multi-component system study

Energy Technology Data Exchange (ETDEWEB)

Liu, Cheng-Chung [Department of Environmental Engineering, National Ilan University, Ilan, 260, Taiwan (China); Wang, Ming-Kuang, E-mail: mkwang@ntu.edu.tw [Department of Agricultural Chemistry, National Taiwan University, Taipei, 106, Taiwan (China); Chiou, Chyow-San; Li, Yuan-Shen [Department of Environmental Engineering, National Ilan University, Ilan, 260, Taiwan (China); Yang, Chia-Yi [Department of Chemical and Materials Engineering, Tamkang University, Tamsui, 251, Taiwan (China); Lin, Yu-An [Department of Animal Science, National Ilan University, Ilan, 260, Taiwan (China)

2009-11-15

Wine-processing waste sludge (WPWS) has been shown to have powerful potential for sorption of some heavy metals (i.e., chromium, lead and nickel) in single-component aqueous solutions. But although most industrial wastewater contains two or more toxic metals, there are few sorption studies on multicomponent metals by WPWS. This study has two goals: (i) conduct competitive adsorption using Cr, Cu and Zn as sorbates and examine their interaction in binary or ternary systems; and (ii) determine the effects of temperature on the kinetic sorption reaction. The sludge tested contained a high amount of organic matter (38%) and had a high cation exchange capacity (CEC, 255 cmol{sub c} kg{sup -1}). Infrared analysis reveals that carboxyl is the main functional group in this WPWS. The {sup 13}C NMR determination indicates alkyl-C and carboxyl-C are major organic functional groups. At steady state, there are about 40.4% (Cr), 35.0% (Cu) and 21.9% (Zn) sorbed in the initial 6.12 mM of single-component solutions. Only pseudo-second-order sorption kinetic model successfully describes the kinetics of sorption for all experimental metals. The rate constants, k{sub 2}, of Cr, Cu and Zn in single-component solutions are 0.016, 0.030 and 0.154 g mg{sup -1} min{sup -1}, respectively. The sorption of metals by WPWS in this competitive system shows the trend: Cr > Cu > Zn. Ions of charge, hydrated radius and electronic configuration are main factors affecting sorption capacity. The least sorption for Zn in this competitive system can be attributed to its full orbital and largest hydrated radius. Though the effect of temperature on Zn sorption is insignificant, high temperature favors the other metallic sorptions, in particular for Cr. However, the Cr sorption is lower than Cu at 10 deg. C. The Cr sorption by WPWS can be higher than that of Cu at 30 deg. and 50 deg. C.

Transformation of Silver Nanoparticles in Sewage Sludge during Incineration.

Science.gov (United States)

Meier, Christoph; Voegelin, Andreas; Pradas del Real, Ana; Sarret, Geraldine; Mueller, Christoph R; Kaegi, Ralf

2016-04-05

Silver nanoparticles (Ag-NP) discharged into the municipal sewer system largely accumulate in the sewage sludge. Incineration and agricultural use are currently the most important strategies for sewage sludge management. Thus, the behavior of Ag-NP during sewage sludge incineration is essential for a comprehensive life cycle analysis and a more complete understanding of the fate of Ag-NP in the (urban) environment. To address the transformation of Ag-NP during sewage sludge incineration, we spiked metallic Ag(0)-NP to a pilot wastewater treatment plant and digested the sludge anaerobically. The sludge was then incinerated on a bench-scale fluidized bed reactor in a series of experiments under variable conditions. Complementary results from X-ray absorption spectroscopy (XAS) and electron microscopy-energy dispersive X-ray (EM-EDX) analysis revealed that Ag(0)-NP transformed into Ag2S-NP during the wastewater treatment, in agreement with previous studies. On the basis of a principal component analysis and subsequent target testing of the XAS spectra, Ag(0) was identified as a major Ag component in the ashes, and Ag2S was clearly absent. The reformation of Ag(0)-NP was confirmed by EM-EDX. The fraction of Ag(0) of the total Ag in the ashes was quantified by linear combination fitting (LCF) of XAS spectra, and values as high as 0.8 were found for sewage sludge incinerated at 800 °C in a synthetic flue gas atmosphere. Low LCF totals (72% to 94%) indicated that at least one relevant reference spectrum was missing in the LCF analysis. The presence of spherical Ag-NP with a diameter of incineration, as demonstrated in this study, needs to be considered in the life cycle assessment of engineered Ag-NP.

Experience with a pilot plant for the irradiation of sewage sludge

International Nuclear Information System (INIS)

Rosopulo, A.; Fiedler, I.; Staerk, H.; Suess, A.; Technische Univ. Muenchen

1975-01-01

Analyses of mineral nutrients and trace elements in sewage sludge over a one year period showed that there are relatively small differences in the content of inorganic constituents. In relation to sewage sludge treatment we found a change in the ratio of NH 4 -N : total N after a heat treatment; this means that the ammonium content increased in 70% of the analysed samples compared to untreated sludge. After radiation treatment of sewage sludge no change can be observed up to a pH of 8. With an increase of the pH-value (>= 8) losses of NH- 4 N can be observed. During the dewatering process of sewage sludge - which is influenced by sewage sludge treatment -, potassium, sodium and ammonium are enriched in the filtering water. While there is a decrease of these alkali elements in the dewatered sewage sludge, nearly no change in the other components can be observed. Studying the availability of mineral compounds and trace elements to plants, results are presented of inorganic nutrients and essential or toxic trace elements of sewage sludge and plants. (orig.) [de

REEMISSION OF MERCURY COMPOUNDS FROM SEWAGE SLUDGE DISPOSAL

Directory of Open Access Journals (Sweden)

Beata Janowska

2016-12-01

Full Text Available The sewage sludge disposal and cultivation methods consist in storage, agricultural use, compost production, biogas production or heat treatment. The sewage sludge production in municipal sewage sludge treatment plants in year 2013 in Poland amounted to 540.3 thousand Mg d.m. The sewage sludge for agricultural or natural use must satisfy chemical, sanitary and environmental safety requirements. The heavy metal content, including the mercury content, determines the sewage sludge disposal method. Mercury has a high chemical activity and biological form compounds with different properties. The properties of the mercury present in sewage sludge or composts, its potential bioavailability depend on its physicochemical forms. Different forms of mercury, which are found in soil and sediments and sewage sludge, may be determined using various techniques sequential extraction. In order to assess the bioavailability the analysis of fractional of mercury in samples of sewage sludge and composts was made. For this purpose the analytical procedure based on a four sequential extraction process was applied. Mercury fractions were classified as exchangeable (EX, base soluble (BS, acids soluble (AS and oxidizable (OX. This article presents the research results on the mercury compounds contents in sewage sludge subjected to drying process, combustion and in composted sewage sludge. During drying and combustion process of the sewage sludge, mercury transforms into volatile forms that could be emitted into the atmosphere. The mercury fractionation in composted sewage sludge proved that mercury in compost occurs mainly in an organic fraction and in a residual fraction that are scarce in the environment.

Heating value characteristics of sewage sludge: a comparative study of different sludge types

International Nuclear Information System (INIS)

Kim, Young-JU.; Kang, Hae-Ok.; Qureshi, T.I.

2005-01-01

Heating value characteristics of three different types of sludge, i.e. domestic sewage sludge, industrial sludge, and industrial + domestic sewage sludge were investigated. Industrial + domestic sewage sludge (thickened) showed the highest heating value (5040 kcal/kg) than other sludge types. This may be due to increased amount of organic matter presents in thickened sludge than de-watered sludge. A gradual increase in organic matter of the sludge was observed with the increase of the moisture contents. Heating value of the sludge having 60% moisture contents was found in the range between 924-1656 kcal/kg and this amount was higher than the minimum heating value (800 kcal/kg) required sustaining auto thermal combustion in sludge incineration process. Energy consumption requirement for pre drying sludge operations revealed that industrial sludge (de-watered) required the minimum cost (13 $/ton of sludge) to make it a sludge of fuel grade (60% W), while mixed sludge cost the highest amount for its pre-drying operations. (author)

Activated Sludge Rheology

DEFF Research Database (Denmark)

Ratkovich, Nicolas Rios; Horn, Willi; Helmus, Frank

2013-01-01

Rheological behaviour is an important fluid property that severely impacts its flow behaviour and many aspects related to this. In the case of activated sludge, the apparent viscosity has an influence on e.g. pumping, hydrodynamics, mass transfer rates, sludge-water separation (settling and filtr...... rheological measurements. Moreover, the rheological models are not very trustworthy and remain very “black box”. More insight in the physical background needs 30 to be gained. A model-based approach with dedicated experimental data collection is the key to address this.......Rheological behaviour is an important fluid property that severely impacts its flow behaviour and many aspects related to this. In the case of activated sludge, the apparent viscosity has an influence on e.g. pumping, hydrodynamics, mass transfer rates, sludge-water separation (settling......, leading to varying results and conclusions. In this paper, a vast amount of papers are critically reviewed with respect to this and important flaws are highlighted with respect to rheometer choice, rheometer settings and measurement protocol. The obtained rheograms from experimental efforts have...

Water washes and caustic leaches of sludge from Hanford Tank S-101 and water washes of sludge from Hanford Tank C-103

International Nuclear Information System (INIS)

Hunt, R.D.; Collins, J.L.; Chase, C.W.

1998-07-01

In 1993, the Department of Energy (DOE) selected the enhanced sludge washing (ESW) process as the baseline for pretreatment of Hanford tank sludges. The ESW process uses a series of water washes and caustic leaches to separate nonradioactive components such as aluminum, chromium, and phosphate from the high-level waste sludges. If the ESW process is successful, the volume of immobilized high-level waste will be significantly reduced. The tests on the sludge from Hanford Tank S-101 focused on the effects of process variables such as sodium hydroxide concentration (1 and 3 M), temperature (70 and 95 C), and leaching time (5, 24, 72, and 168 h) on the efficacy of the ESW process with realistic liquid-to-solid ratios. Another goal of this study was to evaluate the effectiveness of water washes on a sludge sample from hanford Tank C-103. The final objective of this study was to test potential process control monitors during the water washes and caustic leaches with actual sludge. Both 137 Cs activity and conductance were measured for each of the water washes and caustic leaches. Experimental procedures, a discussion of results, conclusions and recommendations are included in this report

Sludge Treatment Evaluation: 1992 Technical progress

International Nuclear Information System (INIS)

Silva, L.J.; Felmy, A.R.; Ding, E.R.

1993-01-01

This report documents Fiscal Year 1992 technical progress on the Sludge Treatment Evaluation Task, which is being conducted by Pacific Northwest Laboratory. The objective of this task is to develop a capability to predict the performance of pretreatment processes for mixed radioactive and hazardous waste stored at Hanford and other US Department of Energy (DOE) sites. Significant cost savings can be achieved if radionuclides and other undesirable constituents can be effectively separated from the bulk waste prior to final treatment and disposal. This work is initially focused on chemical equilibrium prediction of water washing and acid or base dissolution of Hanford single-shell tank (SST) sludges, but may also be applied to other steps in pretreatment processes or to other wastes. Although SST wastes contain many chemical species, there are relatively few constituents -- Na, Al, NO 3 , NO 2 , PO 4 , SO 4 , and F -- contained in the majority of the waste. These constituents comprise 86% and 74% of samples from B-110 and U-110 SSTS, respectively. The major radionuclides of interest (Cs, Sr, Tc, U) are present in the sludge in small molal quantities. For these constituents, and other important components that are present in small molal quantities, the specific ion-interaction terms used in the Pitzer or NRTL equations may be assumed to be zero for a first approximation. Model development can also be accelerated by considering only the acid or base conditions that apply for the key pretreatment steps. This significantly reduces the number of chemical species and chemical reactions that need to be considered. Therefore, significant progress can be made by developing all the specific ion interactions for a base model and an acid dissolution model

Sludge Treatment Evaluation: 1992 Technical progress

Energy Technology Data Exchange (ETDEWEB)

Silva, L J; Felmy, A R; Ding, E R

1993-01-01

This report documents Fiscal Year 1992 technical progress on the Sludge Treatment Evaluation Task, which is being conducted by Pacific Northwest Laboratory. The objective of this task is to develop a capability to predict the performance of pretreatment processes for mixed radioactive and hazardous waste stored at Hanford and other US Department of Energy (DOE) sites. Significant cost savings can be achieved if radionuclides and other undesirable constituents can be effectively separated from the bulk waste prior to final treatment and disposal. This work is initially focused on chemical equilibrium prediction of water washing and acid or base dissolution of Hanford single-shell tank (SST) sludges, but may also be applied to other steps in pretreatment processes or to other wastes. Although SST wastes contain many chemical species, there are relatively few constituents -- Na, Al, NO[sub 3], NO[sub 2], PO[sub 4], SO[sub 4], and F -- contained in the majority of the waste. These constituents comprise 86% and 74% of samples from B-110 and U-110 SSTS, respectively. The major radionuclides of interest (Cs, Sr, Tc, U) are present in the sludge in small molal quantities. For these constituents, and other important components that are present in small molal quantities, the specific ion-interaction terms used in the Pitzer or NRTL equations may be assumed to be zero for a first approximation. Model development can also be accelerated by considering only the acid or base conditions that apply for the key pretreatment steps. This significantly reduces the number of chemical species and chemical reactions that need to be considered. Therefore, significant progress can be made by developing all the specific ion interactions for a base model and an acid dissolution model.

Sludge Incineration. Multiple Hearth. Sludge Treatment and Disposal Course #166. Instructor's Guide [and] Student Workbook.

Science.gov (United States)

Klopping, Paul H.

This lesson introduces the basics of sludge incineration and focuses on the multiple hearth furnace in accomplishing this task. Attention is given to component identification and function process control fundamentals, theory of incineration, safety, and other responsibilites of furnace operation. The material is rather technical and assumes an…

Waste sludge resuspension and transfer: development program

International Nuclear Information System (INIS)

Weeren, H.O.; Mackey, T.S.

1980-02-01

The six Gunite waste tanks at Oak Ridge National Laboratory (ORNL) contain about 400,000 gal of sludge that has precipitated from solution and settled during the 35 years these tanks have been in service. Eventual decommissioning of the tanks has been proposed. The first part of this program is to resuspend the accumulated sludge, to transfer it to new storage tanks in Melton Valley, and to dispose of it by the shale-fracturing process. On the basis of preliminary information, a tentative operational concept was adopted. The sludge in each tank would be resuspended by hydraulic sluicing and pumped from the tank. This resuspended sludge would be treated as necessary to keep the particles in suspension and would be pumped to the new waste-storage tanks. Subsequently the sludge would be pumped from the tanks, combined with a cement-base mix, and disposed of by the shale-fracturing facility. Verification of the feasibility of this concept required development effort on characterization of the sludge and development of techniques for resuspending the sludge and for keeping it in suspension. These development efforts are described in this report. Sections of the report describe both the known properties of the sludge and the tests of grinding methods investigated, discuss tests of various suspenders, describe tests with cement-base mixes, summarize hot-cell tests on actual sludge samples, and describe tests that were made at a mockup of a Gunite tank installation. On the basis of the tests made, it was concluded that reslurrying and resuspension of the sludge is quite feasible and that the suspensions can be made compatible with cement mixes

A potential application of sludge-based catalysts for the anaerobic bio-decolorization of tartrazine dye.

Science.gov (United States)

Athalathil, Sunil; Fortuny, Agusti; Font, Josep; Stüber, Frank; Bengoa, Christophe; Fabregat, Azael

2015-01-01

Two highly efficient (K2CO3/sludge carbon and ZnCl2/sludge carbon) solids were prepared by chemical addition following carbonization at 800 °C and were tested for anaerobic reduction of tartrazine dye in a continuous upflow packed-bed biological reactor, and their performance was compared to that of commercial activated carbon (CAC). The chemical and structural information of the solids was subjected to various characterizations in order to understand the mechanism for anaerobic decolorization, and efficiency for SBCZN800 and SBCPC800 materials was 87% and 74%, respectively, at a short space time (τ) of 2.0 min. A first-order kinetic model fitted the experimental points and kinetic constants of 0.40, 0.92 and 1.46 min(-1) were obtained for SBCZN800, SBCPC800 and CAC, respectively. The experimental results revealed that performance of solids in the anaerobic reduction of tartrazine dye can depend on several factors including chemical agents, carbonization, microbial population, chemical groups and surface chemistry. The Langmuir and Freundlich models are successfully described in the batch adsorption data. Based on these observations, a cost-effective sludge-based catalyst can be produced from harmful sewage sludge for the treatment of industrial effluents.

Dispersed plug flow model for upflow anaerobic sludge bed reactors with focus on granular sludge dynamics

NARCIS (Netherlands)

Kalyuzhnyi, S.V.; Fedorovich, V.V.; Lens, P.N.L.

2006-01-01

A new approach to model upflow anaerobic sludge bed (UASB)-reactors, referred to as a one-dimensional dispersed plug flow model, was developed. This model focusses on the granular sludge dynamics along the reactor height, based on the balance between dispersion, sedimentation and convection using

Economic comparison of sludge irradiation and alternative methods of municipal sludge treatment

International Nuclear Information System (INIS)

Ahlstrom, S.B.; McGuire, H.E.

1977-11-01

The relative economics of radiation treatment and other sludge treatment processes are reported. The desirability of radiation treatment is assessed in terms of cost and the quality of the treated sludge product. The major conclusions of this study are: radiation treatment is a high-level disinfection process. Therefore, it should only be considered if high levels of disinfection are required for widespread reuse of the sludge; the handling, transporting and pathogen growback problems associated with disinfected wet sludge makes it less attractive for reuse than dry sludge; radiation of composted sludge produces a product of similar quality at less cost than any thermal treatment and/or flash drying treatment option for situations where a high degree of disinfection is required; and heavy metal concerns, especially cadmium, may limit the reuse of sludge despite high disinfection levels. It is recommended that radiation treatment of sludge, particularly dry sludge, continue to be studied. A sensitivity analysis investigating the optimal conditions under which sludge irradiation operates should be instigated. Furthermore, costs of adding sludge irradiation to existing sludge treatment schemes should be determined

Sludge Digestion Manual; Handboek Slibgisting

Energy Technology Data Exchange (ETDEWEB)

NONE

2011-09-15

This manual offers a guideline for developing, designing, optimizing and operating sludge digestion installations based on sewage sludge. It also offers tools for solving operation problems [Dutch] Het Handboek is een leidraad voor het ontwikkelen, ontwerpen, optimaliseren en bedrijven van slibgistingsinstallaties voor zuiveringsslib. Ook geeft het handvatten voor het oplossen van operationele problemen.

Analysis of the cement clinker produced with incorporation of petroleum sludge

Science.gov (United States)

Benlamoudi, A.; Kadir, A. Abdul; Khodja, M.; Nuruddin, M. F.

2018-04-01

Very limited researches have been conducted on the incorporation of petroleum sludge waste into cement clinker production even though this waste may contain similar components to those of clinker raw materials. In this research, petroleum sludge was integrated into cement plant as raw material to produce the cement clinker. As results, incorporation of 5% of this waste was able to produce an acceptable quality of cement. Despite the use of petroleum sludge has decreased the properties of the produced clinker, but it still fit the requirements.

Sustainability of Domestic Sewage Sludge Disposal

Directory of Open Access Journals (Sweden)

Claudia Bruna Rizzardini

2014-04-01

Full Text Available Activated sludge is now one of the most widely used biological processes for the treatment of wastewaters from medium to large populations. It produces high amounts of sewage sludge that can be managed and perceived in two main ways: as a waste it is discharged in landfill, as a fertilizer it is disposed in agriculture with direct application to soil or subjected to anaerobic digestion and composting. Other solutions, such as incineration or production of concrete, bricks and asphalt play a secondary role in terms of their degree of diffusion. The agronomical value of domestic sewage sludge is a proved question, which may be hidden by the presence of several pollutants such as heavy metals, organic compounds and pathogens. In this way, the sustainability of sewage sludge agricultural disposal requires a value judgment based on knowledge and evaluation of the level of pollution of both sewage sludge and soil. The article analyzed a typical Italian case study, a water management system of small communities, applying the criteria of evaluation of the last official document of European Union about sewage sludge land application, the “Working Document on Sludge (3rd draft, 2000”. The report brought out good sewage sludge from small wastewater treatment plants and soils quality suggesting a sustainable application.

Recycle of valuable products from oily cold rolling mill sludge

Science.gov (United States)

Liu, Bo; Zhang, Shen-gen; Tian, Jian-jun; Pan, De-an; Liu, Yang; Volinsky, Alex A.

2013-10-01

Oily cold rolling mill (CRM) sludge contains lots of iron and alloying elements along with plenty of hazardous organic components, which makes it as an attractive secondary source and an environmental contaminant at the same time. The compound methods of "vacuum distillation + oxidizing roasting" and "vacuum distillation + hydrogen reduction" were employed for the recycle of oily cold rolling mill sludge. First, the sludge was dynamically vacuum distilled in a rotating furnace at 50 r/min and 600°C for 3 h, which removed almost hazardous organic components, obtaining 89.2wt% ferrous resultant. Then, high purity ferric oxide powders (99.2wt%) and reduced iron powders (98.9wt%) were obtained when the distillation residues were oxidized and reduced, respectively. The distillation oil can be used for fuel or chemical feedstock, and the distillation gases can be collected and reused as a fuel.

Consequences of sludge composition on combustion performance derived from thermogravimetry analysis

Energy Technology Data Exchange (ETDEWEB)

Li, Meiyan; Xiao, Benyi; Wang, Xu; Liu, Junxin, E-mail: jxliu@rcees.ac.cn

2015-01-15

Highlights: • Volatiles, particularly proteins, play a key role in sludge combustion. • Sludge combustion performance varies with different sludge organic concentrations. • Carbohydrates significantly affect the combustion rate in the second stage. • Combustion performance of digested sludge is more negative compared with others. - Abstract: Wastewater treatment plants produce millions of tons of sewage sludge. Sewage sludge is recognized as a promising feedstock for power generation via combustion and can be used for energy crisis adaption. We aimed to investigate the quantitative effects of various sludge characteristics on the overall sludge combustion process performance. Different types of sewage sludge were derived from numerous wastewater treatment plants in Beijing for further thermogravimetric analysis. Thermogravimetric–differential thermogravimetric curves were used to compare the performance of the studied samples. Proximate analytical data, organic compositions, elementary composition, and calorific value of the samples were determined. The relationship between combustion performance and sludge composition was also investigated. Results showed that the performance of sludge combustion was significantly affected by the concentration of protein, which is the main component of volatiles. Carbohydrates and lipids were not correlated with combustion performance, unlike protein. Overall, combustion performance varied with different sludge organic composition. The combustion rate of carbohydrates was higher than those of protein and lipid, and carbohydrate weight loss mainly occurred during the second stage (175–300 °C). Carbohydrates have a substantial effect on the rate of system combustion during the second stage considering the specific combustion feature. Additionally, the combustion performance of digested sewage sludge is more negative than the others.

Consequences of sludge composition on combustion performance derived from thermogravimetry analysis

International Nuclear Information System (INIS)

Li, Meiyan; Xiao, Benyi; Wang, Xu; Liu, Junxin

2015-01-01

Highlights: • Volatiles, particularly proteins, play a key role in sludge combustion. • Sludge combustion performance varies with different sludge organic concentrations. • Carbohydrates significantly affect the combustion rate in the second stage. • Combustion performance of digested sludge is more negative compared with others. - Abstract: Wastewater treatment plants produce millions of tons of sewage sludge. Sewage sludge is recognized as a promising feedstock for power generation via combustion and can be used for energy crisis adaption. We aimed to investigate the quantitative effects of various sludge characteristics on the overall sludge combustion process performance. Different types of sewage sludge were derived from numerous wastewater treatment plants in Beijing for further thermogravimetric analysis. Thermogravimetric–differential thermogravimetric curves were used to compare the performance of the studied samples. Proximate analytical data, organic compositions, elementary composition, and calorific value of the samples were determined. The relationship between combustion performance and sludge composition was also investigated. Results showed that the performance of sludge combustion was significantly affected by the concentration of protein, which is the main component of volatiles. Carbohydrates and lipids were not correlated with combustion performance, unlike protein. Overall, combustion performance varied with different sludge organic composition. The combustion rate of carbohydrates was higher than those of protein and lipid, and carbohydrate weight loss mainly occurred during the second stage (175–300 °C). Carbohydrates have a substantial effect on the rate of system combustion during the second stage considering the specific combustion feature. Additionally, the combustion performance of digested sewage sludge is more negative than the others

Feasibility Study of Neutron Multiplicity Assay for a Heterogeneous Sludge Sample containing Na, Pu and other Impurities

International Nuclear Information System (INIS)

Nakamura, H.; Nakamichi, H.; Mukai, Y.; Yoshimoto, K.; Beddingfield, D.H.

2010-01-01

To reduce radioactivity of liquid waste generated at PCDF, a neutralization precipitation processes of radioactive nuclides by sodium hydroxide is used. We call the precipitate a 'sludge' after calcination. Pu mass in the sludge is normally determined by sampling and DA within the required uncertainty on DIQ. Annual yield of the mass is small but it accumulates and reaches to a few kilograms, so it is declared as retained waste and verified at PIV. A HM-5-based verification is applied for sludge verification. The sludge contains many chemical components. For example, Pu (-10wt%), U, Am, SUS components, halogens, NaNO 3 (main component), residual NaOH, and moisture. They are mixed together as an impure heterogeneous sludge sample. As a result, there is a large uncertainty in the sampling and DA that is currently used at PCDF. In order to improve the material accounting, we performed a feasibility study using neutron multiplicity assay for impure sludge samples. We have measured selected sludge samples using a multiplicity counter which is called FCAS (Fast Carton Assay System) which was designed by JAEA and Canberra. The PCDF sludge materials fall into the category of 'difficult to measure' because of the high levels of impurities, high alpha values and somewhat small Pu mass. For the sludge measurements, it was confirmed that good consistency between Pu mass in a pure sludge standard (PuO 2 -Na 2 U 2 O 7 , alpha=7) and the DA could be obtained. For unknown samples, using 14-hour measurements, we could obtain quite low statistical uncertainty on Doubles (-1%) and Triples (-10%) count rate although the alpha value was extremely high (15-25) and FCAS efficiency was relatively low (40%) for typical multiplicity counters. Despite the detector efficiency challenges and the material challenges (high alpha, low Pu mass, heterogeneous matrix), we have been able to obtain assay results that greatly exceed the accountancy requirements for retained waste materials. We have

Determination of uranium metal concentration in irradiated fuel storage basin sludge using selective dissolution

International Nuclear Information System (INIS)

Delegard, C.H.; Sinkov, S.I.; Chenault, J.W.; Schmidt, A.J.; Pool, K.N.; Welsh, T.L.

2014-01-01

Irradiated uranium metal fuel was stored underwater in the K East and K West storage basins at the US Department of Energy Hanford Site. The uranium metal under damaged cladding reacted with water to generate hydrogen gas, uranium oxides, and spalled uranium metal particles which intermingled with other particulates to form sludge. While the fuel has been removed, uranium metal in the sludge remains hazardous. An expeditious routine method to analyze 0.03 wt% uranium metal in the presence of >30 wt% total uranium was needed to support safe sludge management and processing. A selective dissolution method was designed based on the rapid uranium oxide dissolution but very low uranium metal corrosion rates in hot concentrated phosphoric acid. The uranium metal-bearing heel from the phosphoric acid step then is rinsed before the uranium metal is dissolved in hot concentrated nitric acid for analysis. Technical underpinnings of the selective dissolution method, including the influence of sludge components, were investigated to design the steps and define the reagents, quantities, concentrations, temperatures, and times within the selective dissolution analysis. Tests with simulant sludge proved the technique feasible. Tests with genuine sludge showed a 0.0028 ± 0.0037 wt% (at one standard deviation) uranium metal analytical background, a 0.011 wt% detection limit, and a 0.030 wt% quantitation limit in settled (wet) sludge. In tests using genuine K Basin sludge spiked with uranium metal at concentrations above the 0.030 wt% ± 25 % (relative) quantitation limit, uranium metal recoveries averaged 99.5 % with a relative standard deviation of 3.5 %. (author)

The Effect of Using Sewage Sludge Ash with and without Nano Silica Particles on Properties of Self-compacting Cement Based Materials

Directory of Open Access Journals (Sweden)

Amin Khoshravesh

2014-10-01

Full Text Available Nowadays using pozzolanic materials is crucial as a replacement of needed cement, improving properties of cement based materials and saving costs. On the other hand sewage sludge is harmful to the environment and human health. So in this research the sewage sludge ash has been used as an artificial pozzolan to produce self compacting cement based materials which could be evaluated as a revolution in the concrete industry. The objective of this research was to accelerate the performance of sewage sludge ash by utilizing nano silica particles. This research includes 10 mix designs for self compacting mortar and concrete made up of binary and ternary cementitious blends of sewage sludge ash (0%,5%,10%,15%,20% and nano silica (0%,1%. The results showed that by adding the sewage sludge ash, rheological and mechanical properties of the samples were reduced and for small percentages of sewage sludge ash, the durability characteristics were improved. The results also showed that adding nano silica improved the mechanical and durability properties of self compacting mortar and concrete. Finally in presence of nano silica, the reactivity of the sewage sludge ash was increased and its performance was improved.

Composition and reactivity of ash from sewage sludge

Energy Technology Data Exchange (ETDEWEB)

Willems, M; Pedersen, B; Jorgensen, S S

1976-01-01

Sewage sludge and sludge ash produced at 450 to 1050/sup 0/C in the laboratory or in a multiple hearth incinerator were analyzed by chemical and X-ray diffraction methods. Among the ash components were 23 to 32 percent calcium and magnesium phosphates and the following percentages of heavy metals: Zn 0.9, Cu 0.2, Pb 0.1, Cr 0.07, Ni 0.02, and Cd 0.006. As shown by EDTA-extraction, the reactivity of heavy metals was higher in ash produced at 450/sup 0/C than in dry sludge, but lower in ash produced above 800/sup 0/C. Phosphate in the 800 to 900/sup 0/C samples was dissolved in citric acid but not in citrate.

Alternative Chemical Cleaning Methods for High Level Waste Tanks: Actual Waste Testing with SRS Tank 5F Sludge

Energy Technology Data Exchange (ETDEWEB)

King, William D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Hay, Michael S. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2016-08-30

Solubility testing with actual High Level Waste tank sludge has been conducted in order to evaluate several alternative chemical cleaning technologies for the dissolution of sludge residuals remaining in the tanks after the exhaustion of mechanical cleaning and sludge sluicing efforts. Tests were conducted with archived Savannah River Site (SRS) radioactive sludge solids that had been retrieved from Tank 5F in order to determine the effectiveness of an optimized, dilute oxalic/nitric acid cleaning reagent toward dissolving the bulk non-radioactive waste components. Solubility tests were performed by direct sludge contact with the oxalic/nitric acid reagent and with sludge that had been pretreated and acidified with dilute nitric acid. For comparison purposes, separate samples were also contacted with pure, concentrated oxalic acid following current baseline tank chemical cleaning methods. One goal of testing with the optimized reagent was to compare the total amounts of oxalic acid and water required for sludge dissolution using the baseline and optimized cleaning methods. A second objective was to compare the two methods with regard to the dissolution of actinide species known to be drivers for SRS tank closure Performance Assessments (PA). Additionally, solubility tests were conducted with Tank 5 sludge using acidic and caustic permanganate-based methods focused on the “targeted” dissolution of actinide species.

Washing and caustic leaching of Hanford tank sludges

International Nuclear Information System (INIS)

Lumetta, G.J.; Rapko, B.M.; Colton, N.G.

1994-01-01

Methods are being developed to treat and dispose of large volumes of radioactive wastes stored in underground tanks at the U.S. Department of Energy's Hanford Site. The wastes will be partitioned into high-level waste (HLW) and low-level waste (LLW) fractions. The HLW will be vitrified into borosilicate glass and disposed of in a geologic repository, while the LLW will be immobilized in a glass matrix and will likely be disposed of by shallow burial at the Hanford Site. The wastes must be pretreated to reduce the volume of the HLW fraction, so that vitrification and disposal costs can be minimized. The current baseline process for pretreating Hanford tank sludges is to leach the sludge under caustic conditions, then remove the solubilized components of the sludge by water washing. Tests of this method have been performed with samples taken from several different tanks at Hanford. The results of these tests are presented in terms of the composition of the sludge before and after leaching. X-ray diffraction and scanning electron microscopy coupled with electron dispersive x-ray techniques have been used to identify the phases in the untreated and treated sludges

Biological sludge solubilisation for reduction of excess sludge production in wastewater treatment process.

Science.gov (United States)

Yamaguchi, T; Yao, Y; Kihara, Y

2006-01-01

A novel sludge disintegration system (JFE-SD system) was developed for the reduction of excess sludge production in wastewater treatment plants. Chemical and biological treatments were applied to disintegrate excess sludge. At the first step, to enhance biological disintegration, the sludge was pretreated with alkali. At the second step, the sludge was disintegrated by biological treatment. Many kinds of sludge degrading microorganisms integrated the sludge. The efficiency of the new sludge disintegration system was confirmed in a full-scale experiment. The JFE-SD system reduced excess sludge production by approximately 50% during the experimental period. The quality of effluent was kept at quite a good level. Economic analysis revealed that this system could significantly decrease the excess sludge treatment cost.

Radioactive sludge and wastewater analysis and treatment in the Hungarian VVER-440/213-type NPP

International Nuclear Information System (INIS)

Patzay, G.; Weiser, L.; Feil, F.; Schunk, J.; Patek, G.; Pinter, T.

2010-01-01

It is well known that in the Hungarian VVER-type nuclear power plant Paks the radioactive waste waters are collected in common tanks. These water streams contain radioactive isotopes in ultra-low concentration and inactive compounds as major components (borate 1.7 g/dm 3 , sodium-nitrate 0.4 g/dm 3 , sodium-hydroxide 0.16 g/dm 3 , and oxalate 0.25 g/dm 3 ). These low salinity solutions were evaporated by adding sodium-hydroxide, until 400 g/dm 3 salt content is reached. There is about 6000 m 3 concentrated evaporator bottom residues in the tanks of the reactor. There are some tanks at the power plant containing sludge type radioactive waste containing more or less liquid phase too. The general physical and chemical characteristics (density, pH, total solid, dissolved solid etc.) and chemical and radiochemical composition are important information for volume reduction and solidification treatment of these wastes. We have investigated and constructed a complex analysis system for the radioactive sludge and supernatant analysis, including the physical, as well as the chemical and radiochemical analysis methods. Using well known analysis techniques as ion chromatography, ICP-MS, AAS, gamma-and alpha-spectrometry and chemical alkaline fusion digestion and acidic dissolution methods we could analyze the main inorganic, organic and radioactive components of the sludges and supernatants. Determination of the mass and charge balance for the sludge samples were more difficult then for the supernatant samples. Not only are there assumptions required about the chemical form and the oxidation state of the species present in the sludge, but many of the compounds in the sludge are mixed oxides which are not directly measured. Also, the sludge is actually a slurry with a high water content. The interstitial liquid is in close contact with the sludge, and there are many ionic solubility equilibriums. The anion data for the sludge samples are based on the water soluble anions that

SLUDGE TREATMENT PROJECT PHASE 1 SLUDGE STORAGE OPTIONS. ASSESSMENT OF T PLANT VERSUS ALTERNATE STORAGE FACILITY

International Nuclear Information System (INIS)

Rutherford, W.W.; Geuther, W.J.; Strankman, M.R.; Conrad, E.A.; Rhoadarmer, D.D.; Black, D.M.; Pottmeyer, J.A.

2009-01-01

The CH2M HILL Plateau Remediation Company (CHPRC) has recommended to the U.S. Department of Energy (DOE) a two phase approach for removal and storage (Phase 1) and treatment and packaging for offsite shipment (Phase 2) of the sludge currently stored within the 105-K West Basin. This two phased strategy enables early removal of sludge from the 105-K West Basin by 2015, allowing remediation of historical unplanned releases of waste and closure of the 100-K Area. In Phase 1, the sludge currently stored in the Engineered Containers and Settler Tanks within the 105-K West Basin will be transferred into sludge transport and storage containers (STSCs). The STSCs will be transported to an interim storage facility. In Phase 2, sludge will be processed (treated) to meet shipping and disposal requirements and the sludge will be packaged for final disposal at a geologic repository. The purpose of this study is to evaluate two alternatives for interim Phase 1 storage of K Basin sludge. The cost, schedule, and risks for sludge storage at a newly-constructed Alternate Storage Facility (ASF) are compared to those at T Plant, which has been used previously for sludge storage. Based on the results of the assessment, T Plant is recommended for Phase 1 interim storage of sludge. Key elements that support this recommendation are the following: (1) T Plant has a proven process for storing sludge; (2) T Plant storage can be implemented at a lower incremental cost than the ASF; and (3) T Plant storage has a more favorable schedule profile, which provides more float, than the ASF. Underpinning the recommendation of T Plant for sludge storage is the assumption that T Plant has a durable, extended mission independent of the K Basin sludge interim storage mission. If this assumption cannot be validated and the operating costs of T Plant are borne by the Sludge Treatment Project, the conclusions and recommendations of this study would change. The following decision-making strategy, which is

SLUDGE TREATMENT PROJECT PHASE 1 SLUDGE STORAGE OPTIONS ASSESSMENT OF T PLANT VERSUS ALTERNATE STORAGE FACILITY

Energy Technology Data Exchange (ETDEWEB)

RUTHERFORD WW; GEUTHER WJ; STRANKMAN MR; CONRAD EA; RHOADARMER DD; BLACK DM; POTTMEYER JA

2009-04-29

The CH2M HILL Plateau Remediation Company (CHPRC) has recommended to the U.S. Department of Energy (DOE) a two phase approach for removal and storage (Phase 1) and treatment and packaging for offsite shipment (Phase 2) of the sludge currently stored within the 105-K West Basin. This two phased strategy enables early removal of sludge from the 105-K West Basin by 2015, allowing remediation of historical unplanned releases of waste and closure of the 100-K Area. In Phase 1, the sludge currently stored in the Engineered Containers and Settler Tanks within the 105-K West Basin will be transferred into sludge transport and storage containers (STSCs). The STSCs will be transported to an interim storage facility. In Phase 2, sludge will be processed (treated) to meet shipping and disposal requirements and the sludge will be packaged for final disposal at a geologic repository. The purpose of this study is to evaluate two alternatives for interim Phase 1 storage of K Basin sludge. The cost, schedule, and risks for sludge storage at a newly-constructed Alternate Storage Facility (ASF) are compared to those at T Plant, which has been used previously for sludge storage. Based on the results of the assessment, T Plant is recommended for Phase 1 interim storage of sludge. Key elements that support this recommendation are the following: (1) T Plant has a proven process for storing sludge; (2) T Plant storage can be implemented at a lower incremental cost than the ASF; and (3) T Plant storage has a more favorable schedule profile, which provides more float, than the ASF. Underpinning the recommendation of T Plant for sludge storage is the assumption that T Plant has a durable, extended mission independent of the K Basin sludge interim storage mission. If this assumption cannot be validated and the operating costs of T Plant are borne by the Sludge Treatment Project, the conclusions and recommendations of this study would change. The following decision-making strategy, which is

An Economic comparison of sludge irradiation and alternative methods of municipal sludge treatment

Energy Technology Data Exchange (ETDEWEB)

Ahlstrom, S.B.; McGuire, H.E.

1977-11-01

The relative economics of radiation treatment and other sludge treatment processes are reported. The desirability of radiation treatment is assessed in terms of cost and the quality of the treated sludge product. The major conclusions of this study are: radiation treatment is a high-level disinfection process. Therefore, it should only be considered if high levels of disinfection are required for widespread reuse of the sludge; the handling, transporting and pathogen growback problems associated with disinfected wet sludge makes it less attractive for reuse than dry sludge; radiation of composted sludge produces a product of similar quality at less cost than any thermal treatment and/or flash drying treatment option for situations where a high degree of disinfection is required; and heavy metal concerns, especially cadmium, may limit the reuse of sludge despite high disinfection levels. It is recommended that radiation treatment of sludge, particularly dry sludge, continue to be studied. A sensitivity analysis investigating the optimal conditions under which sludge irradiation operates should be instigated. Furthermore, costs of adding sludge irradiation to existing sludge treatment schemes should be determined.

Recycling of radioactive oil sludge waste into pavement brick

International Nuclear Information System (INIS)

Meor Yusoff Meor Sulaiman; Hishamuddin Hussein; Choo Thye Foo; Nurul Wahida Ahmad Khairuddin; MAsliana MUslimin; Wilfred Sylvester Paulus

2010-01-01

Malaysia produces about 1450 tons of radioactive oil sludge waste per year and there is an urgent need to find a permanent solution to the storage and disposal of this radioactive waste problem. Several treatment methods such bacteria farming, ultracentrifuge, steam reforming and incineration are currently being used but the core issue of the radioactive material in the oil sludge had not been solved. The paper relates a study on utilizing the radioactive component of the oil sludge and turning them into pavement brick. Characteristic study of this radioactive component by XRD and XRF show that it mainly comprised of quartz and anorthite minerals. While the radioactivity analysis by gamma technique shows that more than 90 % of this radioactivity comes from this soil component with Ra-226 and Ra-228 as the main radionuclides. A vitrified brick was then produced from this sediment by mixing it with low radioactive local red clay. The result also shows that the formation of the vitrified layer may be due high content of K in the red clay. Tensile test on the brick shows that it has more than four times the strength of commercial clay brick. Long duration leaching test on the brick also shows that there is no dissolution of radionuclide from the brick. (author)

Availability of uranium present in the sludge generated at two stations of potable water treatment

International Nuclear Information System (INIS)

Munoz-Serrano, A.; Baeza, A.; Salas, A.; Guillen, J.

2013-01-01

During the treatment is carried out in a Station Potable Water Treatment Plant sludge enriched are produced in components that have been removed from the water. The concentration and availability of radionuclides accumulated in a sludge during coagulation-flocculation will condition possible later use, so it is essential to carry out the characterization of sludge and its chemical speciation. (Author)

Sewage sludge disintegration by high-pressure homogenization: a sludge disintegration model.

Science.gov (United States)

Zhang, Yuxuan; Zhang, Panyue; Ma, Boqiang; Wu, Hao; Zhang, Sheng; Xu, Xin

2012-01-01

High-pressure homogenization (HPH) technology was applied as a pretreatment to disintegrate sewage sludge. The effects of homogenization pressure, homogenization cycle number, and total solid content on sludge disintegration were investigated. The sludge disintegration degree (DD(COD)), protein concentration, and polysaccharide concentration increased with the increase of homogenization pressure and homogenization cycle number, and decreased with the increase of sludge total solid (TS) content. The maximum DD(COD) of 43.94% was achieved at 80 MPa with four homogenization cycles for a 9.58 g/L TS sludge sample. A HPH sludge disintegration model of DD(COD) = kNaPb was established by multivariable linear regression to quantify the effects of homogenization parameters. The homogenization cycle exponent a and homogenization pressure exponent b were 0.4763 and 0.7324 respectively, showing that the effect of homogenization pressure (P) was more significant than that of homogenization cycle number (N). The value of the rate constant k decreased with the increase of sludge total solid content. The specific energy consumption increased with the increment of sludge disintegration efficiency. Lower specific energy consumption was required for higher total solid content sludge.

Delisting petition for 300-M saltstone (treated F006 sludge) from the 300-M liquid effluent treatment facility

Energy Technology Data Exchange (ETDEWEB)

1989-04-04

This petition seeks exclusion for stabilized and solidified sludge material generated by treatment of wastewater from the 300-M aluminum forming and metal finishing processes. The waste contains both hazardous and radioactive components and is classified as a mixed waste. The objective of this petition is to demonstrate that the stabilized sludge material (saltstone), when properly disposed, will not exceed the health-based standards for the hazardous constituents. This petition contains sampling and analytical data which justify the request for exclusion. The results show that when the data are applied to the EPA Vertical and Horizontal Spread (VHS) Model, health-based standards for all hazardous waste constituents will not be exceeded during worst case operating and environmental conditions. Disposal of the stabilized sludge material in concrete vaults will meet the requirements pertaining to Waste Management Activities for Groundwater Protection at the Savannah River Site in Aiken, S.C. Documents set forth performance objectives and disposal options for low-level radioactive waste disposal. Concrete vaults specified for disposal of 300-M saltstone (treated F006 sludge) assure that these performance objectives will be met.

Radiation disinfection of sewage sludge and composting of the irradiated sludge

International Nuclear Information System (INIS)

Hashimoto, Shoji; Nishimura, Koichi; Watanabe, Hiromasa; Kawakami, Waichiro

1985-01-01

In the radiation disinfected sewage sludge, its stabilization is necessary with the composting. In this disinfected sludge, there is no need of keeping it at high temperature at the cost of fermentation velocity. The fermentation velocity can thus be set to obtain its maximum value. In sewage sludge utilization of farm land, to prevent the contamination with pathogenic bacteria and the secondary pollution, the radiation disinfection of dehydrated sludge and the composting of the disinfected sludge have been studied. The disinfection effect when an electron accelerator is used for the radiation source is described. Then, the composting of the disinfected sludge is described in chemical kinetics of the microorganisms. (Mori, K.)

Separation and Fixation of Toxic Components in Salt Brines Using a Water-Based Process

International Nuclear Information System (INIS)

Franks, Carrie J.; Quach, Anh P.; Birnie, Dunbar P.; Ela, Wendell P.; Saez, Avelino E.; Zelinski, Brian J.; Smith, Harry D.; Smith, Gary Lynn L.

2004-01-01

Efforts to implement new water quality standards, increase water reuse and reclamation, and minimize the cost of waste storage motivate the development of new processes for stabilizing waste water residuals that minimize waste volume, water content and the long-term environmental risk from related by products. This work explores the use of an aqueous-based emulsion process to create an epoxy/rubber matrix for separating and encapsulating waste components from salt laden, arsenic contaminated, amorphous iron hydrate sludges. Such sludges are generated from conventional water purification precipitation/adsorption processes, used to convert aqueous brine streams to semi-solid waste streams, such as ion exchange/membrane separation, and from other precipitative heavy metal removal operations. In this study, epoxy and polystyrene butadiene (PSB) rubber emulsions are mixed together and then combined with a surrogate sludge. The surrogate sludge consists of amorphous iron hydrate with 1 part arsenic fixed to the surface of the hydrate per 10 parts iron mixed with sodium nitrate and chloride salts and water. The resulting emulsion is cured and dried at 80 C to remove water. Microstructure characterization by electron microscopy confirms that the epoxy/PSB matrix surrounds and encapsulates the arsenic laden amorphous iron hydrate phase while allowing the salt to migrate to internal and external surfaces of the sample. Salt extraction studies indicate that the porous nature of the resulting matrix promotes the separation and removal of as much as 90% of the original salt content in only one hours time. Long term leaching studies based on the use of the infinite slab diffusion model reveal no evidence of iron migration or, by inference, arsenic migration, and demonstrate that the diffusion coefficients of the unextracted salt yield leachability indices within regulations for non-hazardous landfill disposal. Because salt is the most mobile species, it is inferred that arsenic

Environmental application of gamma technology: Update on the Canadian sludge irradiator

Science.gov (United States)

Swinwood, Jean F.; Fraser, Frank M.

1993-10-01

Waste treatment and disposal technologies have recently been subjected to increasing public and regulatory scrutiny. Concern for the environment and a heightened awareness of potential health hazards that could result from insufficient or inappropriate waste handling methods have combined to push waste generators in their search for new treatment alternatives. Gamma technology can offer a new option for the treatment of potentially infectious wastes, including municipal sewage sludge. Sewage sludge contains beneficial plant nutrients and a high organic component that make it ideal as a soil conditioning agent or fertilizer bulking material. It also carries potentially infectious microorganisms which limit opportunities for beneficial recycling of sludges. Gamma irradiation-disinfection of these sludges offers a reliable, fast and efficient method for safe sludge recycling. Nordion International's Market Development Division was created in 1987 as part of a broad corporate reorganization. It was given an exclusive mandate to develop new applications of gamma irradiation technology and markets for these new applications. Nordion has since explored and developed opportunities in food irradiation, pharmaceutical/cosmetic products irradiation, biomedical waste sterilization, airline waste disinfection, and sludge disinfection for recycling. This paper focuses on the last of these -a proposed sludge recycling facility that incorporates a cobalt 60 sludge irradiator.

Treatment of off-gas evolved from thermal decomposition of sludge waste

International Nuclear Information System (INIS)

Doo-Seong Hwang; Yun-Dong Choi; Gyeong-Hwan Jeong; Jei-Kwon Moon

2013-01-01

Korea Atomic Energy Research Institute (KAERI) started a decommissioning program of a uranium conversion plant. The treatment of the sludge waste, which was generated during the operation of the plant, is one of the most important tasks in the decommissioning program of the plant. The major compounds of sludge waste are nitrate salts and uranium. The sludge waste is denitrated by thermal decomposition. The treatment of off-gas evolved from the thermal decomposition of nitrate salts in the sludge waste is investigated. The nitrate salts in the sludge were decomposed in two steps: the first decomposition is due to the ammonium nitrate, and the second is due to the sodium and calcium nitrate and calcium carbonate. The components of off-gas from the decomposition of ammonium nitrate at low temperature are NH 3 , N 2 O, NO 2 , and NO. In addition, the components from the decomposition of sodium and calcium nitrate at high temperature are NO 2 and NO. Off-gas from the thermal decomposition is treated by the catalytic oxidation of ammonia and selective catalytic reduction (SCR). Ammonia is converted into nitrogen oxides through the oxidation catalyst and all nitrogen oxides are removed by SCR treatment besides nitrous oxide, which is greenhouse gas. An additional process is needed to remove nitrous oxide, and the feeding rate of ammonia in SCR should be controlled properly for evolved nitrogen oxides. (author)

Sludge recovery apparatus

International Nuclear Information System (INIS)

Marmo, A.R.

1979-01-01

Sludge recovery machine comprising a hollow centrifuge, a vertical pipe for feeding in a liquid containing sludge and a sliding rake pressing against the internal wall of the centrifuge to dislodge and move the sludge, a power drive for spinning the centrifuge at high speed and a rotating drying table to take the sludge and dry it [fr

Excess sludge reduction in activated sludge processes by integrating ultrasound treatment

International Nuclear Information System (INIS)

Perez-Elvira, S.; Fdz-Polanco, M.; Plaza, F. I.; Garralon, G.; Fdz-Polanco, F.

2009-01-01

Biological sludge produced in the activated sludge process can be minimised modifying the water line, the sludge line or the final disposal strategy. Selecting the water line the general idea is to reduce the sludge producing the yield coefficient by means of the called lysis cryptic growth process. The main techniques referenced in literature are onization, chlorination and chemical and heat treatment. Ultrasounds are widely used to increase anaerobic biodegradability but are not reported as system to control excess sludge production. (Author)

Anaerobic granular sludge and biofilm reactors

DEFF Research Database (Denmark)

Skiadas, Ioannis V.; Gavala, Hariklia N.; Schmidt, Jens Ejbye

2003-01-01

by the immobilization of the biomass, which forms static biofilms, particle-supported biofilms, or granules depending on the reactor's operational conditions. The advantages of the high-rate anaerobic digestion over the conventional aerobic wastewater treatment methods has created a clear trend for the change......-rate anaerobic treatment systems based on anaerobic granular sludge and biofilm are described in this chapter. Emphasis is given to a) the Up-flow Anaerobic Sludge Blanket (UASB) systems, b) the main characteristics of the anaerobic granular sludge, and c) the factors that control the granulation process...

Degradation of polyvinyl chloride (PVC) / hydrolyzed collagen (HC) blends active sludge test.

Science.gov (United States)

Agafiţei, Gabriela-Elena; Pascu, Mihaela; Cazacu, Georgeta; Vasile, Cornelia

2008-01-01

Biodegradable polymers represent a solution for the environment protection: they decrease the landfill space, by declining the petrochemical sources, and offer also an alternative solution for the recycling. The behavior during degradation in the presence of active sludge of some polyvinyl chloride (PVC) based blends with variable content of hydrolyzed collagen (HC) has been followed. Some samples were subjected to UV irradiation, for 30 hours. The modifications induced in the environment by the polymer systems (pH variation, bacterial composition), as well as the changes of the properties of the blends (weight losses, aspect etc.) were studied. During the first moments of degradation in active sludge, all the samples absorbed water, behavior which favored the biodegradation. The bacteriological analysis of the sludge indicates the presence of some microbiological species. Generally, the populations of microorganisms decrease, excepting the sulphito-reducing anaerobic bacteria, the actinomycetes and other anaerobic bacteria. PVC/HC blends are degraded with a significant rate in active sewage sludge. More susceptible for the degradation are the UV irradiated blends. After the migration of the components with a small molecular mass in the environment, the natural polymer is degraded. The degradation effect increases with the content in the natural polymer.

Effects of different sludge disintegration methods on sludge moisture distribution and dewatering performance.

Science.gov (United States)

Jin, Lingyun; Zhang, Guangming; Zheng, Xiang

2015-02-01

A key step in sludge treatment is sludge dewatering. However, activated sludge is generally very difficult to be dewatered. Sludge dewatering performance is largely affected by the sludge moisture distribution. Sludge disintegration can destroy the sludge structure and cell wall, so as change the sludge floc structure and moisture distribution, thus affecting the dewatering performance of sludge. In this article, the disintegration methods were ultrasound treatment, K2FeO4 oxidation and KMnO4 oxidation. The degree of disintegration (DDCOD), sludge moisture distribution and the final water content of sludge cake after centrifuging were measured. Results showed that three disintegration methods were all effective, and K2FeO4 oxidation was more efficient than KMnO4 oxidation. The content of free water increased obviously with K2FeO4 and KMnO4 oxidations, while it decreased with ultrasound treatment. The changes of free water and interstitial water were in the opposite trend. The content of bounding water decreased with K2FeO4 oxidation, and increased slightly with KMnO4 oxidation, while it increased obviously with ultrasound treatment. The water content of sludge cake after centrifuging decreased with K2FeO4 oxidation, and did not changed with KMnO4 oxidation, but increased obviously with ultrasound treatment. In summary, ultrasound treatment deteriorated the sludge dewaterability, while K2FeO4 and KMnO4 oxidation improved the sludge dewaterability. Copyright © 2014. Published by Elsevier B.V.

A comparison between model and rule based control of a periodic activated sludge process

DEFF Research Database (Denmark)

Isaacs, Steven Howard; Thornberg, D.

1997-01-01

Two strategies for control of nitrogen removal in an alternating activated sludge plant are compared. One is based on simple model predictions determining the cycle length at the beginning of each cycle. The other is based on simple rules relating present ammonia and nitrate concentrations. Both ...

Production of bacterial cellulose and enzyme from waste fiber sludge

Science.gov (United States)

2013-01-01

Background Bacterial cellulose (BC) is a highly crystalline and mechanically stable nanopolymer, which has excellent potential as a material in many novel applications, especially if it can be produced in large amounts from an inexpensive feedstock. Waste fiber sludge, a residue with little or no value, originates from pulp mills and lignocellulosic biorefineries. A high cellulose and low lignin content contributes to making the fiber sludge suitable for bioconversion, even without a thermochemical pretreatment step. In this study, the possibility to combine production of BC and hydrolytic enzymes from fiber sludge was investigated. The BC was characterized using field-emission scanning electron microscopy and X-ray diffraction analysis, and its mechanical properties were investigated. Results Bacterial cellulose and enzymes were produced through sequential fermentations with the bacterium Gluconacetobacter xylinus and the filamentous fungus Trichoderma reesei. Fiber sludges from sulfate (SAFS) and sulfite (SIFS) processes were hydrolyzed enzymatically without prior thermochemical pretreatment and the resulting hydrolysates were used for BC production. The highest volumetric yields of BC from SAFS and SIFS were 11 and 10 g/L (DW), respectively. The BC yield on initial sugar in hydrolysate-based medium reached 0.3 g/g after seven days of cultivation. The tensile strength of wet BC from hydrolysate medium was about 0.04 MPa compared to about 0.03 MPa for BC from a glucose-based reference medium, while the crystallinity was slightly lower for BC from hydrolysate cultures. The spent hydrolysates were used for production of cellulase with T. reesei. The cellulase activity (CMCase activity) in spent SAFS and SIFS hydrolysates reached 5.2 U/mL (87 nkat/mL), which was similar to the activity level obtained in a reference medium containing equal amounts of reducing sugar. Conclusions It was shown that waste fiber sludge is a suitable raw material for production of

Disintegration impact on sludge digestion process.

Science.gov (United States)

Dauknys, Regimantas; Rimeika, Mindaugas; Jankeliūnaitė, Eglė; Mažeikienė, Aušra

2016-11-01

The anaerobic sludge digestion is a widely used method for sludge stabilization in wastewater treatment plant. This process can be improved by applying the sludge disintegration methods. As the sludge disintegration is not investigated enough, an analysis of how the application of thermal hydrolysis affects the sludge digestion process based on full-scale data was conducted. The results showed that the maximum volatile suspended solids (VSS) destruction reached the value of 65% independently on the application of thermal hydrolysis. The average VSS destruction increased by 14% when thermal hydrolysis was applied. In order to have the maximum VSS reduction and biogas production, it is recommended to keep the maximum defined VSS loading of 5.7 kg VSS/m(3)/d when the thermal hydrolysis is applied and to keep the VSS loading between 2.1-2.4 kg VSS/m(3)/d when the disintegration of sludge is not applied. The application of thermal hydrolysis leads to an approximately 2.5 times higher VSS loading maintenance comparing VSS loading without the disintegration; therefore, digesters with 1.8 times smaller volume is required.

Applicability and trends of anaerobic granular sludge treatment processes

International Nuclear Information System (INIS)

Lim, Seung Joo; Kim, Tak-Hyun

2014-01-01

Anaerobic granular sludge treatment processes have been continuously developed, although the anaerobic sludge granulation process was not clearly understood. In this review, an upflow anaerobic sludge blanket (UASB), an expanded granule sludge blanket (EGSB), and a static granular bed reactor (SGBR) were introduced as components of a representative anaerobic granular sludge treatment processes. The characteristics and application trends of each reactor were presented. The UASB reactor was developed in the late 1970s and its use has been rapidly widespread due to the excellent performance. With the active granules, this reactor is able to treat various high-strength wastewaters as well as municipal wastewater. Most soluble industrial wastewaters can be efficiently applied using a UASB. The EGSB reactor was developed owing to give more chance to contact between wastewater and the granules. Dispersed sludge is separated from mature granules using the rapid upward velocity in this reactor. The EGSB reactor shows the excellent performance in treating low-strength and/or high-strength wastewater, especially under low temperatures. The SGBR, developed at Iowa State University, is one of anaerobic granular sludge treatment processes. Although the configuration of the SGBR is very simple, the performance of this system is similar to that of the UASB or EGSB reactor. The anaerobic sludge granulation processes showed excellent performance for various wastewaters at a broad range of organic loading rate in lab-, pilot-scale tests. This leads to erect thousands of full-scale granular processes, which has been widely operated around the world. -- Highlights: • Anaerobic sludge granulation is a key parameter for maintaining granular processes. • Anaerobic granular digestion processes are applicable for various wastewaters. • The UASB is an economic high-rate anaerobic granular process. • The EGSB can treat high-strength wastewater using expanding granules. • The SGBR is

Effect of chemical composition on the flocculation dynamics of latex-based synthetic activated sludge

International Nuclear Information System (INIS)

Tan Phong Nguyen; Hankins, Nicholas P.; Hilal, Nidal

2007-01-01

This study investigates the effect of calcium, alginate, fibrous cellulose, and pH on the flocculation dynamics and final properties of synthetic activated sludges. A laboratory-scale batch reactor, fed with standard synthetic sludges was used. The effects of varying calcium concentration (5-25 mM), alginate concentration (25-125 mg/L), fibrous cellulose concentration (0.2-0.8 g/L) and pH (3-9) on the sludge characteristics were studied by varying one parameter whilst keeping the others constant. The results from experiments indicated that the calcium, alginate, fibrous cellulose, and pH had the critical effect on the aggregation rate, flocs size, and made the improvement of the final properties of sludge. Dynamic measurements have established the optimum conditions for floc formation and can accurately reflect the state of formation of the synthetic activated sludge flocs. These correlate well with measurements of settleability and turbidity of the synthetic activated sludge. The results of this study support the bonding theory and indicate that formation of cations-polymer complexes and polymer gelation are important means of flocculation. The development of synthetic activated sludges is suggested also to be a possible surrogate for studying the final properties of activated sludge

Influence of nanoparticles on the polymer-conditioned dewatering of wastewater sludges.

Science.gov (United States)

Boyle, N J; Evans, G M

2013-01-01

The effect of using small-scale, high surface area, nanoparticles to supplement polymer-conditioned wastewater sludge dewatering was investigated. Aerobically digested sludge and waste activated sludge sourced from the Hunter Valley, NSW, Australia, were tested with titanium dioxide nanoparticles. The sludge samples were dosed with the nanoparticles in an attempt to adsorb a component of the charged biopolymer surfactants present naturally in sludge. The sludge was conditioned with a cationic polymer. The dewatering characteristics were assessed by measuring the specific resistance to filtration through a modified time-to-filter testing apparatus. The solids content of the dosed samples was determined by a mass balance and compared to the original solids content in the activated sludge. Test results indicated that nanoparticle addition modified the structure of the sludge and provided benefits in terms of the dewatering rate. The samples dosed with nanoparticles exhibited faster water removal, indicating a more permeable filter cake and hence more permeable sludge. A concentration of 2-4% nanoparticles was required to achieve a noticeable benefit. As a comparison, the sludge samples were also tested with a larger particle size, powdered activated carbon (PAC). It was found that the PAC did provide some minor benefits to sludge dewatering but was outperformed by the nanoparticles. The solids content of the final sludge was increased by a maximum of up to 0.6%. The impact of the order sequence of particles and polymer was also investigated. It was found that nanoparticles added before polymer addition provided the best dewatering performance. This outcome was consistent with current theories and previous research through the literature. An economic analysis was undertaken to confirm the viability of the technology for implementation at a full-scale plant. It was found that, currently, this technology is unlikely to be favourable unless the nanoparticles can be

The role and control of sludge age in biological nutrient removal activated sludge systems.

Science.gov (United States)

Ekama, G A

2010-01-01

The sludge age is the most fundamental and important parameter in the design, operation and control of biological nutrient removal (BNR) activated sludge (AS) systems. Generally, the better the effluent and waste sludge quality required from the system, the longer the sludge age, the larger the biological reactor and the more wastewater characteristics need to be known. Controlling the reactor concentration does not control sludge age, only the mass of sludge in the system. When nitrification is a requirement, sludge age control becomes a requirement and the secondary settling tanks can no longer serve the dual purpose of clarifier and waste activated sludge thickeners. The easiest and most practical way to control sludge age is with hydraulic control by wasting a defined proportion of the reactor volume daily. In AS plants with reactor concentration control, nitrification fails first. With hydraulic control of sludge age, nitrification will not fail, rather the plant fails by shedding solids over the secondary settling tank effluent weirs.

Rheology of Savannah River Site Tank 51 HLW radioactive sludge

International Nuclear Information System (INIS)

Ha, B.C.

1993-01-01

Savannah River Site (SRS) Tank 51 HLW radioactive sludge represents a major portion of the first batch of sludge to be vitrified in the Defense Waste Processing Facility (DWPF) at SRS. The rheological properties of Tank 51 sludge will determine if the waste sludge can be pumped by the current DWPF process cell pump design and the homogeneity of melter feed slurries. The rheological properties of Tank 51 sludge and sludge/frit slurries at various solids concentrations were measured remotely in the Shielded Cells Operations (SCO) at the Savannah River Technology Center (SRTC) using a modified Haake Rotovisco viscometer system. Rheological properties of Tank 51 radioactive sludge/Frit 202 slurries increased drastically when the solids content was above 41 wt %. The yield stresses of Tank 51 sludge and sludge/frit slurries fall within the limits of the DWPF equipment design basis. The apparent viscosities also fall within the DWPF design basis for sludge consistency. All the results indicate that Tank 51 waste sludge and sludge/frit slurries are pumpable throughout the DWPF processes based on the current process cell pump design, and should produce homogeneous melter feed slurries

Radioactivity in sludge: tank cleaning procedures and sludge disposal

International Nuclear Information System (INIS)

Bradley, D.A.

1995-01-01

In the oil and gas industry management of alpha-active sludge is made more complex by the presence of hydrocarbons and heavy metals. This presentation discusses the origin of radioactivity in sludge, management of risk in terms of safe working procedures, storage and possible disposal options. The several options will generally involve aspects of dilution or of concentration; issues to be discussed will include sludge farming, bioremediation and incineration. (author)

Strength, leachability and microstructure characteristics of cement-based solidified plating sludge

International Nuclear Information System (INIS)

Asavapisit, Suwimol; Naksrichum, Siripat; Harnwajanawong, Naraporn

2005-01-01

The solidification of the stabilized zinc-cyanide plating sludge was carried out using ordinary Portland cement (OPC) and pulverized fuel ash (PFA) as solidification binders. The plating sludge were used at the level of 0%, 10%, 20% and 30% dry weight, and PFA was used to replace OPC at 0%, 10%, 20% and 30% dry weight, respectively. Experimental results showed that a significant reduction in strength was observed when the plating sludge was added to both the OPC and OPC/PFA binders, but the negative effect was minimized when PFA was used as part substitute for OPC. SEM observation reveals that the deposition of the plating sludge on the surface of the clinkers and PFA could be the cause for hydration retardation. In addition, calcium zinc hydroxide hydrate complex and the unreacted di- and tricalcium silicates were the major phases in X-ray diffraction (XRD) patterns of the solidified plating waste hydrated for 28 days, although the retardation effect on hydration reactions but Cr concentration in toxicity characteristic leaching procedure (TCLP) leachates was lower than the U.S. EPA regulatory limit

Relationship between centrifugation and drying of sludge and the organic halogens

Directory of Open Access Journals (Sweden)

Karel Hrich

2010-01-01

Full Text Available This work is focused on determination of adsorbable organic halogens (AOX concentration in the digested sludge from the sewage treatment plant and the losses of this component during dewatering and drying of sludge. Drying of the sludge from wastewater treatment plant is not extended too much in Czech Republic. In this work, the AOX are monitored, because AOX is one of the limits restraining use of the sludge on an agricultural land. Another reason is technological demand for using the sludge in cement processing, because chlorine in AOX can cause decrease in a heat transfer effect in a cement kiln. It is clear from the results that both centrifuged and dried sludge from the sewage treatment plant Brno fulfilled limits for using sludge on agriculture land. They can also be composted, in case they meet other requirements. If not, it is a possibility of co-incineration in cement kiln. In such case, limit for total chlorine including the AOX is required too. This limit was not exceeded. Another aim was to calculate a mass balance of AOX during the centrifugation and drying processes. It was found out, that after centrifugation the main part of AOX remained in the centrifuged sludge (96.4 %. The rest was drawn-off with reject water. 60 % of AOX in the reject water were dissolved compounds. A similar situation occurred during the drying process. More than 99 % of AOX was bound in the dried sludge. The air and vaporised water contained such quantity of AOX, which corresponded with the amount of the dust in the air and the amount of particles of sludge in vaporised water.

EXTRACELLULAR PROTEINS PRODUCED BY DIFFERENT SPECIES OF THE FUNGUS TRICHODERMA ON SECONDARY PAPER MILL SLUDGE SUBSTRATE

Directory of Open Access Journals (Sweden)

Ida Vaskova,

2012-01-01

Full Text Available Kraft pulping is the most commonly used pulping process in the pulp and paper industry. In this process wood chips are chemically delignified using sodium sulfide and sodium hydroxide. Delignification is usually followed by mechanical fiberization and a bleaching process of the resulting wood pulp. In addition to lignin-free wood pulp, this process also produces waste that contains residues of used chemicals, lignin, cellulose, hemicelluloses, and small amounts of other wood components. Because of the worldwide large-scale production of paper, the sludge from paper mills contributes significantly to environmental pollution. Although there have been great efforts being made to utilize this lignin-rich material, sludge is mostly disposed in landfills or incinerated in a boiler. This research project used secondary sludge as a substrate for 7 wood-decay fungi taxonomically belonging to the genus Trichoderma. The examined fungi expressed the capability of consuming sludge components as a carbon source to produce extracellular proteins. The proteins were separated by gel electrophoresis. Before and after fungi cultivation, the sludge was analyzed by Fourier transform infrared spectroscopy (FTIR.

The Potential in Bioethanol Production From Waste Fiber Sludges in Pulp Mill-Based Biorefineries

Science.gov (United States)

Sjöde, Anders; Alriksson, Björn; Jönsson, Leif J.; Nilvebrant, Nils-Olof

Industrial production of bioethanol from fibers that are unusable for pulp production in pulp mills offers an approach to product diversification and more efficient exploitation of the raw material. In an attempt to utilize fibers flowing to the biological waste treatment, selected fiber sludges from three different pulp mills were collected, chemically analyzed, enzymatically hydrolyzed, and fermented for bioethanol production. Another aim was to produce solid residues with higher heat values than those of the original fiber sludges to gain a better fuel for combustion. The glucan content ranged between 32 and 66% of the dry matter. The lignin content varied considerably (1-25%), as did the content of wood extractives (0.2-5.8%). Hydrolysates obtained using enzymatic hydrolysis were found to be readily fermentable using Saccharomyces cerevisiae. Hydrolysis resulted in improved heat values compared with corresponding untreated fiber sludges. Oligomeric xylan fragments in the solid residue obtained after enzymatic hydrolysis were identified using matrix-assisted laser desorption ionization-time of flight and their potential as a new product of a pulp mill-based biorefinery is discussed.

K basins sludge removal sludge pretreatment system

International Nuclear Information System (INIS)

Chang, H.L.

1997-01-01

The Spent Nuclear Fuels Program is in the process of planning activities to remove spent nuclear fuel and other materials from the 100-K Basins as a remediation effort for clean closure. The 105 K- East and K-West Basins store spent fuel, sludge, and debris. Sludge has accumulated in the 1 00 K Basins as a result of fuel oxidation and a slight amount of general debris being deposited, by settling, in the basin water. The ultimate intent in removing the sludge and fuel is to eliminate the environmental risk posed by storing fuel at the K Basins. The task for this project is to disposition specific constituents of sludge (metallic fuel) to produce a product stream through a pretreatment process that will meet the requirements, including a final particle size acceptable to the Tank Waste Remediation System (TWRS). The purpose of this task is to develop a preconceptual design package for the K Basin sludge pretreatment system. The process equipment/system is at a preconceptual stage, as shown in sketch ES-SNF-01 , while a more refined process system and material/energy balances are ongoing (all sketches are shown in Appendix C). Thus, the overall process and 0535 associated equipment have been conservatively selected and sized, respectively, to establish the cost basis and equipment layout as shown in sketches ES- SNF-02 through 08

Synthetic fibers as an indicator of land application of sludge

International Nuclear Information System (INIS)

Zubris, Kimberly Ann V.; Richards, Brian K.

2005-01-01

Synthetic fabric fibers have been proposed as indicators of past spreading of wastewater sludge. Synthetic fiber detectability was examined in sludges (dewatered, pelletized, composted, alkaline-stabilized) and in soils from experimental columns and field sites applied with those sludge products. Fibers (isolated by water extraction and examined using polarized light microscopy) were detectable in sludge products and in soil columns over 5 years after application, retaining characteristics observed in the applied sludge. Concentrations mirrored (within a factor of 2) predictions based on soil dilution. Fibers were detectable in field site soils up to 15 years after application, again retaining the characteristics seen in sludge products. Concentrations correlated with residual sludge metal concentration gradients in a well-characterized field site. Fibers found along preferential flow paths and/or in horizons largely below the mixed layer suggest some potential for translocation. Synthetic fibers were shown to be rapid and semi-quantitative indicators of past sludge application. - Synthetic fabric fibers present in wastewater sludge are a semi-quantitative long-term indicator of past sludge application in soils

Sludge minimization technologies - an overview

Energy Technology Data Exchange (ETDEWEB)

Oedegaard, Hallvard

2003-07-01

The management of wastewater sludge from wastewater treatment plants represents one of the major challenges in wastewater treatment today. The cost of the sludge treatment amounts to more that the cost of the liquid in many cases. Therefore the focus on and interest in sludge minimization is steadily increasing. In the paper an overview is given for sludge minimization (sludge mass reduction) options. It is demonstrated that sludge minimization may be a result of reduced production of sludge and/or disintegration processes that may take place both in the wastewater treatment stage and in the sludge stage. Various sludge disintegration technologies for sludge minimization are discussed, including mechanical methods (focusing on stirred ball-mill, high-pressure homogenizer, ultrasonic disintegrator), chemical methods (focusing on the use of ozone), physical methods (focusing on thermal and thermal/chemical hydrolysis) and biological methods (focusing on enzymatic processes). (author)

Filterability of membrane bioreactor (MBR) sludge: impacts of polyelectrolytes and mixing with conventional activated sludge.

Science.gov (United States)

Yigit, Nevzat O; Civelekoglu, Gokhan; Cinar, Ozer; Kitis, Mehmet

2010-01-01

The main objective of this work was to investigate the filterability of MBR sludge and its mixture with conventional activated sludge (CAS). In addition, the impacts of type and dose of various polyelectrolytes, filter type and sludge properties on the filterability of both MBR and Mixed sludges were determined. Specific cake resistance (SCR) measured by the Buchner funnel filtration test apparatus and the solids content of the resulting sludge cake were used to assess the dewaterability of tested sludges. The type of filter paper used in Buchner tests affected the results of filterability for MBR, CAS and Mixed sludges. SCR values and optimum polyelectrolyte doses increased with increasing MLSS concentrations in the MBR, which suggested that increase in MLSS concentrations accompanied by increases in EPS and SMP concentrations and a shift toward smaller particles caused poorer dewaterability of the MBR sludge. The significant differences observed among the filterability of CAS and MBR sludges suggested that MLSS alone is not a good predictor of sludge dewaterability. Combining CAS and MBR sludges at different proportions generally improved their dewaterability. Combining MBR sludges having typically high MLSS and EPS concentrations with CAS having much lower MLSS concentrations may be an option for full-scale treatment plants experiencing sludge dewaterability problems. Better filterability and higher cake dry solids were achieved with cationic polyelectrolytes compared to anionic and non-ionic ones for all sludge types tested.

Time-dependent evolution of olive mill wastewater sludge organic and inorganic components and resident microbiota in multi-pond evaporation system.

Science.gov (United States)

Jarboui, Raja; Chtourou, Mohamed; Azri, Chafai; Gharsallah, Néji; Ammar, Emna

2010-08-01

The physico-chemical and microbiological characterizations of olive mill wastewater sludge (OMWS) were investigated in five OMW evaporation ponds of the open-pond system in Sfax (Tunisia), during the olive oil production period in 2004. Time-dependent changes in both physico-chemical parameters and the microbiota were investigated. Mathematical models and principal component analysis (PCA) were used to establish the correlations between the studied parameters. During the effluent time-dependent changes in the ponds, the result of OMWS analysis showed an increase of sludge index (SI), ash content, total solids (TS), volatile solids (VS), ethyl acetate extractive (EAE) and total phosphorus (Total P), as well as microbial flora especially the yeasts and moulds. The SI, TS, VS and Total P changes with time fit a simple linear equation, while EAE, phenols and NH(4)(+) fit a second-degree polynomial model. The PCA analysis exhibited three correlated groups. The first group included temperature, ash content, evaporation, SI, TS, VS, Total P, EAE, yeasts and moulds. The second group was made by bacteria and moisture; and the third group by NH(4)(+), oil and phenol. Such modelling might be of help in the prediction of OMW changes in natural evaporation ponds. (c) 2010 Elsevier Ltd. All rights reserved.

Design characteristics of the Sludge Mobilization System

International Nuclear Information System (INIS)

McMahon, C.L.

1990-01-01

Radioactive waste stored in underground tanks at the West Valley Demonstration Project is being processed into low-level waste and solidified in cement. High-level waste also stored underground will be vitrified and solidified into canistered glass logs. To move the waste from where it resides at the Waste Tank Farm to the Vitrification Facility requires equipment to prepare the storage tanks for low-level and high-level waste processing, equipment to mobilize and mix the radioactive sludge into a homogeneous slurry, and equipment to transfer the slurry for vitrification. The design of the Sludge Mobilization System has incorporated the necessary components to effect the preparation and transfer of waste in five operational phases. The first phase of the Sludge Mobilization System, which began in 1987, prepared the waste tanks to process radioactive liquid for delivery to the Cement Solidification System and to support the mobilization equipment. The second phase, beginning in 1991, will wash the sludge that remains after the liquid supernatant is decanted to prepare it for mobilization operations. The third phase will combine the contents of various waste tanks into one tank. The fourth phase will resuspend and mix the contents of the high-level waste tank. The fifth and final phase of the Sludge Mobilization System will entail transferring the waste mixture to the Vitrification Facility for processing into glass logs. Provisions for recycling the waste streams or slurries within the tank farm or for returning process streams to the Waste Tank Farm from the Vitrification Facility are also included in the final phase. This document addresses the Sludge Mobilization System equipment design characteristics in terms of its use in each of the five operational phases listed above

An exploration of the effect and interaction mechanism of bisphenol A on waste sludge hydrolysis with multi-spectra, isothermal titration microcalorimetry and molecule docking.

Science.gov (United States)

Hou, Guangying; Zhang, Rui; Hao, Xiaoyan; Liu, Chunguang

2017-07-05

An increasing amount of bisphenol A (BPA) is being produced and used, then discharged into sewage treatment plants and accumulated in sludge or soil, when the sludge is used as fertilizer. Accumulation of BPA in sludge or soil causes poisoning to the enzyme, which affects the biological treatment of sludge and the circulation and conversion of materials in soil. In this research, effect of BPA on sludge hydrolysis is studied from the respect of concentration and components of soluble organic matter in sludge, using three-dimensional fluorescence spectra. In order to illuminate the interaction mechanism, toxic effect of BPA on α-Amylase (a model of hydrolase in sludge) is investigated with multi-spectra, isothermal titration microcalorimetry and molecule docking at the molecular level. Results show that the secondary structure of α-Amylase and the microenvironment of amino acid residue in α-Amylase are changed. The molecular docking study and ITC results show that hydrophobic bond and hydrogen bond exist in the interaction between BPA and α-Amylase. Based on the above analysis and enzyme activity assay, sludge hydrolysis is inhibited due to the denaturation of α-Amylase with BPA exposure. Copyright © 2017 Elsevier B.V. All rights reserved.

The exploitation of swamp plants for dewatering liquid sewage sludge

Directory of Open Access Journals (Sweden)

Jiří Šálek

2006-01-01

Full Text Available The operators of little rural wastewater treatment plants have been interested in economic exploitation of sewage sludge in local conditions. The chance is searching simply and natural ways of processing and exploitation stabilized sewage sludge in agriculture. Manure substrate have been obtained by composting waterless sewage sludge including rest plant biomass after closing 6–8 years period of filling liquid sewage sludge to the basin. Main attention was focused on exploitation of swamp plants for dewatering liquid sewage sludge and determination of influence sewage sludge on plants, intensity and course of evapotranspiration and design and setting of drying beds. On the base of determined ability of swamp plants evapotranspiration were edited suggestion solutions of design and operation sludge bed facilities in the conditions of small rural wastewater treatment plant.

Production of hydrogen in a granular sludge-based anaerobic continuous stirred tank reactor

Energy Technology Data Exchange (ETDEWEB)

Show, Kuan-Yeow [Faculty of Engineering and Science, University of Tunku Abdul Rahman, 53300 Setapak, Kuala Lumpur (Malaysia); Zhang, Zhen-Peng; Tay, Joo-Hwa [School of Civil and Environmental Engineering, Nanyang Technological University, 639798 (Singapore); Institute of Environmental Science and Engineering, Nanyang Technological University, 637723 (Singapore); Tee Liang, David [Institute of Environmental Science and Engineering, Nanyang Technological University, 637723 (Singapore); Lee, Duu-Jong [Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan, RO (China); Jiang, Wen-Ju [Department of Environmental Science and Engineering, Sichuan University, Chengdu 610065 (China)

2007-12-15

An investigation on biohydrogen production was conducted in a granular sludge-based continuous stirred tank reactor (CSTR). The reactor performance was assessed at five different glucose concentrations of 2.5, 5, 10, 20 and 40 g/L and four hydraulic retention times (HRTs) of 0.25, 0.5, 1 and 2 h, resulting in the organic loading rates (OLRs) ranged between 2.5 and 20 g-glucose/L h. Carbon flow was traced by analyzing the composition of gaseous and soluble metabolites as well as the cell yield. Butyrate, acetate and ethanol were found to be the major soluble metabolite products in the biochemical synthesis of hydrogen. Carbon balance analysis showed that more than half of the glucose carbon was converted into unidentified soluble products at an OLR of 2.5 g-glucose/L h. It was found that high hydrogen yields corresponded to a sludge loading rate in between 0.6 and 0.8 g-glucose/g-VSS h. Substantial suppression in hydrogen yield was noted as the sludge loading rate fell beyond the optimum range. It is deduced that decreasing the sludge loading rate induced the metabolic shift of biochemical reactions at an OLR of 2.5 g-glucose/L h, which resulted in a substantial reduction in hydrogen yield to 0.36-0.41 mol-H{sub 2}/mol-glucose. Optimal operation conditions for peak hydrogen yield (1.84 mol-H{sub 2}/mol-glucose) and hydrogen production rate (3.26 L/L h) were achieved at an OLR of 20 g-glucose/L h, which corresponded to an HRT of 0.5 h and an influent glucose concentration of 10 g/L. Influence of HRT and substrate concentration on the reactor performance was interrelated and the adverse impact on hydrogen production was noted as substrate concentration was higher than 20 g/L or HRT was shorter than 0.5 h. The experimental study indicated that a higher OLR derived from appropriate HRTs and substrate concentrations was desirable for hydrogen production in such a granule-based CSTR. (author)

Extracellular polymeric substances (EPS) producing bacterial strains of municipal wastewater sludge: isolation, molecular identification, EPS characterization and performance for sludge settling and dewatering.

Science.gov (United States)

Bala Subramanian, S; Yan, S; Tyagi, R D; Surampalli, R Y

2010-04-01

Wastewater treatment plants often face the problems of sludge settling mainly due to sludge bulking. Generally, synthetic organic polymer and/or inorganic coagulants (ferric chloride, alum and quick lime) are used for sludge settling. These chemicals are very expensive and further pollute the environment. Whereas, the bioflocculants are environment friendly and may be used to flocculate the sludge. Extracellular polymeric substances (EPS) produced by sludge microorganisms play a definite role in sludge flocculation. In this study, 25 EPS producing strains were isolated from municipal wastewater treatment plant. Microorganisms were selected based on EPS production properties on solid agar medium. Three types of EPS (slime, capsular and bacterial broth mixture of both slime and capsular) were harvested and their characteristics were studied. EPS concentration (dry weight), viscosity and their charge (using a Zetaphoremeter) were also measured. Bioflocculability of obtained EPS was evaluated by measuring the kaolin clay flocculation activity. Six bacterial strains (BS2, BS8, BS9, BS11, BS15 and BS25) were selected based on the kaolin clay flocculation. The slime EPS was better for bioflocculation than capsular EPS and bacterial broth. Therefore, extracted slime EPS (partially purified) from six bacterial strains was studied in terms of sludge settling [sludge volume index (SVI)] and dewatering [capillary suction time (CST)]. Biopolymers produced by individual strains substantially improved dewaterability. The extracted slime EPS from six different strains were partially characterized. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

Critical operational parameters for zero sludge production in biological wastewater treatment processes combined with sludge disintegration.

Science.gov (United States)

Yoon, Seong-Hoon; Lee, Sangho

2005-09-01

Mathematical models were developed to elucidate the relationships among process control parameters and the effect of these parameters on the performance of anoxic/oxic biological wastewater processes combined with sludge disintegrators (A/O-SD). The model equations were also applied for analyses of activated sludge processes hybrid with sludge disintegrators (AS-SD). Solubilization ratio of sludge in the sludge disintegrator, alpha, hardly affected sludge reduction efficiencies if the biomass was completely destructed to smaller particulates. On the other hand, conversion efficiency of non-biodegradable particulates to biodegradable particulates, beta, significantly affected sludge reduction efficiencies because beta was directly related to the accumulation of non-biodegradable particulates in bioreactors. When 30% of sludge in the oxic tank was disintegrated everyday and beta was 0.5, sludge reduction was expected to be 78% and 69% for the A/O-SD and AS-SD processes, respectively. Under this condition, the sludge disintegration number (SDN), which is the amount of sludge disintegrated divided by the reduced sludge, was calculated to be around 4. Due to the sludge disintegration, live biomass concentration decreased while other non-biodegradable particulates concentration increased. As a consequence, the real F/M ratio was expected to be much higher than the apparent F/M. The effluent COD was maintained almost constant for the range of sludge disintegration rate considered in this study. Nitrogen removal efficiencies of the A/O-SD process was hardly affected by the sludge disintegration until daily sludge disintegration reaches 40% of sludge in the oxic tank. Above this level of sludge disintegration, autotrophic biomass concentration decreases overly and TKN in the effluent increases abruptly in both the A/O-SD and AS-SD processes. Overall, the trends of sludge reduction and effluent quality according to operation parameters matched well with experimental results

Effects of Sludge-amendment on Mineralization of Pyrene and Microorganisms in Sludge and Soil

DEFF Research Database (Denmark)

Klinge, C; Gejlsbjerg, B; Ekelund, Flemming

2001-01-01

. Sludge-amendment enhanced the mineralization of pyrene in the soil compared to soil without sludge, and the most extensive mineralization was observed when the sludge was kept in a lump. The number of protozoa, heterotrophic bacteria and pyrene-mineralizing bacteria was much higher in the sludge compared...... to the soil. The amendment of sludge did not affect the number of protozoa and bacteria in the surrounding soil, which indicated that organic contaminants in the sludge had a little effect on the number of protozoa and bacteria in the surrounding soil...

Sludge Batch 7B Qualification Activities With SRS Tank Farm Sludge

International Nuclear Information System (INIS)

Pareizs, J.; Click, D.; Lambert, D.; Reboul, S.

2011-01-01

projected noble metals content for SB7b. Characterization was performed on the Tank 51 SB7b samples and SRNL performed DWPF simulations using the Tank 40 SB7b material. This report documents: (1) The preparation and characterization of the Tank 51 SB7b and Tank 40 SB7b samples. (2) The performance of a DWPF Chemical Process Cell (CPC) simulation using the SB7b Tank 40 sample. The simulation included a Sludge Receipt and Adjustment Tank (SRAT) cycle, where acid was added to the sludge to destroy nitrite and reduce mercury, and a Slurry Mix Evaporator (SME) cycle, where glass frit was added to the sludge in preparation for vitrification. The SME cycle also included replication of five canister decontamination additions and concentrations. Processing parameters were based on work with a nonradioactive simulant. (3) Vitrification of a portion of the SME product and characterization and durability testing (as measured by the Product Consistency Test (PCT)) of the resulting glass. (4) Rheology measurements of the SRAT receipt, SRAT product, and SME product. This program was controlled by a Task Technical and Quality Assurance Plan (TTQAP), and analyses were guided by an Analytical Study Plan. This work is Technical Baseline Research and Development (R and D) for the DWPF. It should be noted that much of the data in this document has been published in interoffice memoranda. The intent of this technical report is bring all of the SB7b related data together in a single permanent record and to discuss the overall aspects of SB7b processing.

Synergistic and alkaline stability studies of mixtures of simulated high level waste sludge with selected energetic compounds

International Nuclear Information System (INIS)

Fondeur, F.F.

2000-01-01

This study examined the stability of mercury oxalate and mercury fulminate in alkaline sludge simulating Savannah River Site waste. These compounds represent two classes of energetic compounds previously speculated as potential components in sludge stored without a supernatant liquid

A new electrokinetic technology for revitalization of oily sludge

Energy Technology Data Exchange (ETDEWEB)

Habibi, S.

2004-07-01

Oily sludge is a mixture of hydrocarbons, water, metals and suspended fine solids. The petroleum industry is faced with the challenge of handling large volumes of such sludge whose properties depend on the nature of the crude oil, the processing capacity, the down-stream capacities and the design of effluent treatment plants. The management of oily sludge is both complicated and costly due to its complex composition. For that reason, this study developed a method to improve the separation of phases to allow for greater reuse of oily sludge. The study focused on the use of electrokinetic phenomena for the remediation of oily sludge. An amphoteric surfactant was used to evaluate the effect of surfactant on the electrokinetic mobilization or organic contaminants in oily sludge. A series of electrokinetic cell tests were conducted with varying electrical potentials for a 32 day period. Electrical parameters were measured on a daily basis and samples were collected at specific time intervals for UV/VIS and FTIR analysis. The study involved a range of electrokinetic processes such as electrocoagulation, electro-coalescence, desorption, electrophoresis and electro-osmosis. Study results were used to evaluate the thermodynamics of the proposed process and new theories on the behaviour of colloidal components of oily sludge were derived. The study indicated that there is an excellent separation of water, hydrocarbon and solid phases. Since the recovered solid phase has a high hydrocarbon content, it can be recycled for other processes. Some of the volatile hydrocarbons that were released during the process can also be captured and burned as a fuel. The separated water had a low concentration of hydrocarbon and could be sent to wastewater treatment plants.

Reinforcement of natural rubber hybrid composites based on marble sludge/Silica and marble sludge/rice husk derived silica

Directory of Open Access Journals (Sweden)

Khalil Ahmed

2014-03-01

Full Text Available A research has been carried out to develop natural rubber (NR hybrid composites reinforced with marble sludge (MS/Silica and MS/rice husk derived silica (RHS. The primary aim of this development is to scrutinize the cure characteristics, mechanical and swelling properties of such hybrid composite. The use of both industrial and agricultural waste such as marble sludge and rice husk derived silica has the primary advantage of being eco-friendly, low cost and easily available as compared to other expensive fillers. The results from this study showed that the performance of NR hybrid composites with MS/Silica and MS/RHS as fillers is extremely better in mechanical and swelling properties as compared with the case where MS used as single filler. The study suggests that the use of recently developed silica and marble sludge as industrial and agricultural waste is accomplished to provide a probable cost effective, industrially prospective, and attractive replacement to the in general purpose used fillers like china clay, calcium carbonate, and talc.

Effect of seed sludge on characteristics and microbial community of aerobic granular sludge.

Science.gov (United States)

Song, Zhiwei; Pan, Yuejun; Zhang, Kun; Ren, Nanqi; Wang, Aijie

2010-01-01

Aerobic granular sludge was cultivated by using different kinds of seed sludge in sequencing batch airlift reactor. The influence of seed sludge on physical and chemical properties of granular sludge was studied; the microbial community structure was probed by using scanning electron microscope and polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). The results showed that seed sludge played an important role on the formation of aerobic granules. Seed sludge taken from beer wastewater treatment plant (inoculum A) was more suitable for cultivating aerobic granules than that of sludge from municipal wastewater treatment plant (inoculum B). Cultivated with inoculum A, large amount of mature granules formed after 35 days operation, its SVI reached 32.75 mL/g, and SOUR of granular sludge was beyond 1.10 mg/(g x min). By contrast, it needed 56 days obtaining mature granules using inoculum B. DGGE profiles indicated that the dominant microbial species in mature granules were 18 and 11 OTU when inoculum A and B were respectively employed as seed sludge. The sequencing results suggested that dominant species in mature granules cultivated by inoculum A were Paracoccus sp., Devosia hwasunensi, Pseudoxanthomonas sp., while the dominant species were Lactococcus raffinolactis and Pseudomonas sp. in granules developed from inoculum B.

Bases for a sewage sludge treatment plant by irradiation in Mexico

International Nuclear Information System (INIS)

Alcantara, Jaime M.; Cruz, Arturo C.

1997-01-01

A good place for the first sludge irradiator in Mexico would be the Toluca Norte sewage water treatment plant. This plant has a definitive biological treatment, and handles only domestic wastewater and assures therefore good and stead sewage sludge quality, and has capacity do deliver sufficient sludge (approximately 22,000 ton.y -1 or 70 ton.d -1 ) to the irradiator. Capital and operating cost calculations for a sewage sludge plant by irradiation in Mexico were done using a mathematical model considering a 50 k W electron linear accelerator of 10 MeV beam energy, an irradiation dose of 5 kGy, a treatment capacity of 346 ton.d -1 , an absorption efficiency of 40%, an electricity consumption of 400 k W, an operating mode of 325 days per year and one shift per day. Total annual operating costs is estimated to be $1,007,900 for treating 346 ton.d -1 with irradiation dose of 5 kGy, including both fixed ($664,000) and variable costs ($343,920). The unit cost at maximum utilization was obtained as $9.00 per ton. (author). 16 refs., 3 tabs

Enhancement of biogas production from sewage sludge by addition of grease trap sludge

International Nuclear Information System (INIS)

Grosser, A.; Neczaj, E.

2016-01-01

Highlights: • Addition of grease trap sludge is interesting option for sewage sludge digestion. • Co-digestion of grease trap sludge and sewage sludge improved efficiency of process. • The anaerobic digestion can be carried out at short hydraulic retention time. • Long chain fatty acids concentration was below the ranges for inhibition of anaerobic digestion. - Abstract: Despite having many benefits, a low degree of volatile solids removal as well as long retention time are the main factors limiting the performance of the anaerobic digestion. Co-digestion of sewage sludge with other organic waste (for example fat rich materials) is one of the few potential ways to enhance the performance of the anaerobic digestion. In this article, the effects of adding fatty rich materials on the performance and stability of semi-continuous anaerobic digestion of sewage sludge were investigated on a 6 l laboratory-scale reactor (working volume equal to 5.5 l). The reactor was operated in a semi-continuous mode with a hydraulic retention time of 10 days. The data presented in this paper relate to the period in which the grease trap sludge accounted for 10, 12, 14, 16 and 18% of the mixture on the volatile solids basis. The results clearly indicate that the addition of fat rich materials like grease trap sludge can lead to a satisfactory increase in biogas yield in digester treating sewage sludge. The results showed that co-digestion can enhance the biogas yield by 28–82% compared to anaerobic digestion of sewage sludge alone (control sample). Moreover, the addition of grease trap sludge to digesters resulted in increased volatile solids removal from 44.38% (control sample) to 57.77% (feedstock with 14% addition of grease trap sludge). It was found that the increase of grease trap sludge in the feedstock had a direct impact on the biogas production and methane yield. This proposal has also been confirmed by statistical analysis such as Pearson correlation coefficients and

Impact of sludge properties on solid-liquid separation of activated sludge

DEFF Research Database (Denmark)

Christensen, Morten Lykkegaard

2016-01-01

Solid-liquid separation of activated sludge is important both directly after the biological treatment of wastewater and for sludge dewatering. The separation of solid from the treated wastewater can be done by clarifiers (conventional plants) or membrane (MBR). Further, part of the sludge is taken...... out from the proces and usually dewatered before further handling. The separation process is costly. Moreover, the separation process depends on the composition and the properties of the sludge. The best separation is obtained for sludge that contains strong, compact flocs without single cells...... and dissolved extracellular polymeric substances (EPS). Polyvalent ions improve the floc strangth and improve the separation whereas monovalent ions (e.g. from road salt, sea water intrusion and industry) reduces impair the separation. Further high pH impairs the separation process due to floc disintegration...

Wasting Away: To Sludge or Not to Sludge?

Directory of Open Access Journals (Sweden)

L Nicolle

2001-01-01

Full Text Available Following a century of high standards of sanitation, food and water safety in North America are often taken for granted. Recent outbreaks of illness attributed to food and water contamination, however, have challenged this complacency. Now, sludge is added to the list of concerns. Sewage sludge is the muddy substance that remains after the treatment of municipal sewage. This material includes not only human waste, but also household and industrial toxic wastes disposed of in local sewers. Federal and provincial Canadian regulations support the use of this material as fertilizer, within acceptable guidelines, as does the Environmental Protection Agency in the United States. The safety of sludge, however, is questioned by some individuals and groups. Specifically, the risk of infectious agents and toxins to workers or other exposed individuals, and the potential for heavy metals and organic chemicals to be transferred from sludge-treated fields into crops are concerns.

Aerobic granular sludge : Scaling up a new technology

NARCIS (Netherlands)

De Kreuk, M.K.

2006-01-01

Most conventional wastewater treatment plants need a large surface area for the treatment of their sewage. This is due to the open structure of the biomass used to convert the polluting components in wastewater. Because of the flocculated growth, sludge concentrations in reaction tanks are low and

Tank 5 Model for Sludge Removal Analysis

International Nuclear Information System (INIS)

LEE, SI

2004-01-01

Computational fluid dynamics methods have been used to develop and provide slurry pump operational guidance for sludge heel removal in Tank 5. Flow patterns calculated by the model were used to evaluate the performance of various combinations of operating pumps and their orientation under steady-state indexed and transient oscillation modes. A model used for previous analyses has been updated to add the valve housing distribution piping and pipe clusters of the cooling coil supply system near pump no. 8 to the previous tank Type-I model. In addition, the updated model included twelve concrete support columns. This model would provide a more accurate assessment of sludge removal capabilities. The model focused on removal of the sludge heel located near the wall of Tank 5 using the two new slurry pumps. The models and calculations were based on prototypic tank geometry and expected normal operating conditions as defined by Tank Closure Project Engineering. Computational fluid dynamics models of Tank 5 with different operating conditions were developed using the FLUENT (trademark) code. The modeling results were used to assess the efficiency of sludge suspension and removal operations in the 75-ft tank. The models employed a three-dimensional approach, a two-equation turbulence model, and an approximate representation of flow obstructions. The calculated local velocity was used as a measure of sludge removal and mixing capability. For the simulations, modeling calculations were performed with indexed pump orientations until an optimum flow pattern near the potential location of the sludge heel was established for sludge removal. The calculated results demonstrated that the existing slurry pumps running at 3801 gpm flowrate per nozzle could remove the sludge from the tank with a 101 in liquid level, based on a historical minimum sludge suspension velocity of 2.27 ft/sec. The only exception is the region within maximum 4.5 ft distance from the tank wall boundary at the

The influence of clay fineness upon sludge recycling in a ceramic matrix

Science.gov (United States)

Szőke, A. M.; Muntean, M.; Sándor, M.; Brotea, L.

2016-04-01

The feasibility of sludge recycling in the ceramic manufacture was evaluated through laboratory testing. Such residues have similar chemical and mineralogical composition with the raw mixture of the green ceramic body used in construction. Several ceramic masses with clay and various proportion of sludge have been synthesized and then characterized by their physical-mechanical properties. The fineness of the clay, the main component of the green ceramic body, has been considered for every raw mixture. The proportion of the sludge waste addition depends on the clay fineness and the sintering capacity also, increases with the clay fineness. The ceramic properties, particularly, the open porosity, and mechanical properties, in presence of small sludge proportion (7, 20%) shows small modification. The introduction of such waste into building ceramic matrix (bricks, tiles, and plates) has a very good perspective.

Compressibility of the fouling layer formed by membrane bioreactor sludge and supernatant

DEFF Research Database (Denmark)

Jørgensen, Mads Koustrup; Poorasgari, Eskandar; Christensen, Morten Lykkegaard

Membrane bioreactors (MBR) are increasingly used for wastewater treatment as they give high effluent quality, low footprint and efficient sludge degradation. However, the accumulation and deposition of sludge components on and within the membrane (fouling) limits the widespread application of MBR....... Compressibility of the gel layer was studied in a dead-end filtration system, whereas the compressibility of a fouling layer formed by MBR sludge was studied in a submerged system hollow sheet membrane by TMP stepping. It was shown that the fouling layer formed by the MBR sludge was highly compressible within....... Hence, for MBR systems operated at constant flux mode, the applied pressure should be increased over time, to compensate for the lower permeability. Increasing applied pressure causes compression of the fouling layer and results in a more severe permeability decline [1]. In a general view, the fouling...

Types and treatment of sewage sludges: Practice in the Federal Republic of Germany

International Nuclear Information System (INIS)

Tabasaran, M.O.

1975-01-01

The sludge that is formed by the various processes in the sewage treatment plant consists mainly of water with a small amount of organic and inorganic suspended solids. It contains pathogenic agents and biological inhibitors, and must be prepared and brought into a form where it is less dangerous to the environment. The de-watering of the sludge is the first step in sludge handling. The solids content of the raw sludge, which is usually between 5 and 10%, can be increased by gravity thickening to 15%, by centrifuging or straining-band-pressing up to 30%, and by pressure-filtration up to 40%. The process of drying enables a substance with almost no moisture to be obtained. Generally the sludge will be either mixed before de-watering with coagulation agencies, or preheated, or its colloidal components biochemically oxidized in order to accelerate the withdrawal of the water. One of the most common methods of disposal is the transport of sludge to a land filling, usually together with the solid refuse of the community. For this purpose the moisture content of the sludge should not be more than 60 to 70 percent. The disposal of sludge into the sea can be practised in coastal towns, but the ecological effects of this kind of sludge removal are still disputed. More expedient is the agricultural utilization of sludge, particularly if the sludge is composted together with a carbon carrier such as city refuse which would make it a very suitable soil improver. In the Federal Republic of Germany the wet oxidation of sludge is applied in a few cases. The most common process is anaerobic alkaline digestion. The incineration of sludge is more economical than drying, but still too, expensive in comparison with other approved processes. (author)

Preparing sewage sludge for land application or surface disposal: A guide for preparers of sewage sludge on the monitoring, record keeping, and reporting requirements of the federal standards for the use of disposal of sewage sludge, 40 CFR part 503

Energy Technology Data Exchange (ETDEWEB)

1993-08-01

The document focuses on the monitoring, recordkeeping, and reporting requirements that apply to persons who prepare sewage sludge or a material derived from sewage sludge. It defines persons who prepare sewage sludge and then summarizes their general responsibilities. USEPA promulgated at 40 CFR Part 503 Phase 1 of the risk-based regulations that govern the final use or disposal of sewage sludge. The intent of the Federal program is to ensure that the use or disposal of sewage sludge occurs in a way that protects both human health and the environment. The Part 503 regulation establishes general requirements, pollutant limits, operational standards, and management practices, as well as monitoring, recordkeeping, and reporting requirements. These requirements apply to sewage sludge that is land applied, placed on a surface disposal site, or incinerated in a sewage sludge-only incinerator.

Summary report on the Y-12 Sludge Detoxification Demonstration project

International Nuclear Information System (INIS)

Jolley, R.L.; Hollenbeck, P.E.; Kennerly, J.M.; Singh, S.P.N.

1994-07-01

The Y-12 Sludge Detoxification Demonstration was conducted in late 1988 at the Oak Ridge Gaseous Diffusion Plant (subsequently renamed the K-25 Site). The erstwhile Waste Management Technology Center (WMTC) managed the conduct of this waste treatment technology to assist the US Department of Energy/Oak Ridge Operations (DOE/ORO) in implementing the DOE Model. This demonstration was the first project selected by the Hazardous Waste Remedial Actions Program (HAZWRAP)(and funded by DOE) in which a private-sector vendor was contracted to demonstrate an innovative treatment process for treating some of the Oak Ridge Site's radioactive mixed wastes to enable their environmentally compliant disposal. Chem-Nuclear Systems, Inc. (CNSI) was the private-sector vendor selected to demonstrate its X*TRAX trademark process. Briefly, the X*TRAX trademark process consisted of thermally treating the sludge in an inert atmosphere (to remove the volatile components) to yield a dry residue (containing the nonvolatilized sludge components) and condensed liquids. The dry residue can then be immobilized in cementitious matrix for delisting and disposal in an industrial landfill; the condensed liquids can be disposed in, for example, an incinerator

SLUDGE WASHING AND DEMONSTRATION OF THE DWPF FLOWSHEET IN THE SRNL SHIELDED CELLS FOR SLUDGE BATCH 5 QUALIFICATION

Energy Technology Data Exchange (ETDEWEB)

Pareizs, J; Cj Bannochie, C; Damon Click, D; Dan Lambert, D; Michael Stone, M; Bradley Pickenheim, B; Amanda Billings, A; Ned Bibler, N

2008-11-10

Sludge Batch 5 (SB5) is predominantly a combination of H-modified (HM) sludge from Tank 11 that underwent aluminum dissolution in late 2007 to reduce the total mass of sludge solids and aluminum being fed to the Defense Waste Processing Facility (DWPF) and Purex sludge transferred from Tank 7. Following aluminum dissolution, the addition of Tank 7 sludge and excess Pu to Tank 51, Liquid Waste Operations (LWO) provided the Savannah River National Laboratory (SRNL) a 3-L sample of Tank 51 sludge for SB5 qualification. SB5 qualification included washing the sample per LWO plans/projections (including the addition of a Pu/Be stream from H Canyon), DWPF Chemical Process Cell (CPC) simulations, waste glass fabrication (vitrification), and waste glass chemical durability evaluation. This report documents: (1) The washing (addition of water to dilute the sludge supernatant) and concentration (decanting of supernatant) of the Tank 51 qualification sample to adjust sodium content and weight percent insoluble solids to Tank Farm projections. (2) The performance of a DWPF CPC simulation using the washed Tank 51 sample. This includes a Sludge Receipt and Adjustment Tank (SRAT) cycle, where acid is added to the sludge to destroy nitrite and remove mercury, and a Slurry Mix Evaporator (SME) cycle, where glass frit is added to the sludge in preparation for vitrification. The SME cycle also included replication of five canister decontamination additions and concentrations. Processing parameters for the CPC processing were based on work with a non radioactive simulant. (3) Vitrification of a portion of the SME product and Product Consistency Test (PCT) evaluation of the resulting glass. (4) Rheology measurements of the initial slurry samples and samples after each phase of CPC processing. This work is controlled by a Task Technical and Quality Assurance Plan (TTQAP) , and analyses are guided by an Analytical Study Plan. This work is Technical Baseline Research and Development (R

Wastewater and sludge management and research in Oman: An overview.

Science.gov (United States)

Jaffar Abdul Khaliq, Suaad; Ahmed, Mushtaque; Al-Wardy, Malik; Al-Busaidi, Ahmed; Choudri, B S

2017-03-01

It is well recognized that management of wastewater and sludge is a critical environmental issue in many countries. Wastewater treatment and sludge production take place under different technical, economic, and social contexts, thus requiring different approaches and involving different solutions. In most cases, a regular and environmentally safe wastewater treatment and associated sludge management requires the development of realistic and enforceable regulations, as well as treatment systems appropriate to local circumstances. The main objective of this paper is to provide useful information about the current wastewater and sludge treatment, management, regulations, and research in Oman. Based on the review and discussion, the wastewater treatment and sludge management in Oman has been evolving over the years. Further, the land application of sewage sludge should encourage revision of existing standards, regulations, and policies for the management and beneficial use of sewage sludge in Oman. Wastewater treatment and sludge management in Oman have been evolving over the years. Sludge utilization has been a challenge due to its association with human waste. Therefore, composting of sewage sludge is the best option in agriculture activities. Sludge and wastewater utilization can add up positively in the economic aspects of the country in terms of creating jobs and improving annual income rate. The number of research projects done on wastewater reuse and other ongoing ones related to the land application of sewage sludge should encourage revision of existing standards, regulations, and policies for the management and beneficial use of sewage sludge in Oman.

Performance of Sandy Dry Beds for sludge dewatering

International Nuclear Information System (INIS)

Al-Muzaini, S.

2003-01-01

Sludge produced by the Jahra treatment plant was assessed. The assessment was directed at determining the performance of sand drying beds. The assessment of quality of the sludge produced was based on the standards for land application of sewage sludge. Analyses were carried out for trace heavy metals and bacteria. The results of analyses showed that the sludge produced was high in organic matter and sand content but low in heavy metals. The collected data indicated that the sand drying beds at the Jahra treatment plant are at present inadequate to handle the projected sludge production. The investigation showed that the sand drying beds are fully used and the plant will require 3-4 times the capacity of the existing drying beds when the plant becomes fully operational. In addition, these sand drying beds are subjected to uncontrollable conditions such as temperature, rainfall and sludge drainage rate. Thus, sand drying beds have become less popular as a dewatering system. This paper evaluates the performance of the existing sand drying beds and suggests the most appropriate technology to alleviate the above mentioned problems. (author)

Comparison of the co-gasification of sewage sludge and food wastes and cost-benefit analysis of gasification- and incineration-based waste treatment schemes.

Science.gov (United States)

You, Siming; Wang, Wei; Dai, Yanjun; Tong, Yen Wah; Wang, Chi-Hwa

2016-10-01

The compositions of food wastes and their co-gasification producer gas were compared with the existing data of sewage sludge. Results showed that food wastes are more favorable than sewage sludge for co-gasification based on residue generation and energy output. Two decentralized gasification-based schemes were proposed to dispose of the sewage sludge and food wastes in Singapore. Monte Carlo simulation-based cost-benefit analysis was conducted to compare the proposed schemes with the existing incineration-based scheme. It was found that the gasification-based schemes are financially superior to the incineration-based scheme based on the data of net present value (NPV), benefit-cost ratio (BCR), and internal rate of return (IRR). Sensitivity analysis was conducted to suggest effective measures to improve the economics of the schemes. Copyright © 2016 Elsevier Ltd. All rights reserved.

Bioproducts for Sludge Reduction in Activated Sludge Systems Treating Oil Refinery Wastewater

Directory of Open Access Journals (Sweden)

Alexandre V.M.F.

2016-03-01

Full Text Available The use of bioproducts that change the cellular metabolism and reduce microbial growth without affecting the organic matter removal is very promising for reducing the amount of sludge in wastewater treatment systems. In this study, two bioproducts were evaluated and compared with a well-known chemical (2,4-DiNitroPhenol – DNP in activated sludge treating petroleum refinery wastewater. In batch experiments, 10 mg/L of DNP, 0.8 mg/L of a bioproduct based on Folic Acid (FA and 10 mg/L of a bioproduct based on Stress Proteins (SP led to 30.6%, 43.2% and 29.8% lower disposal of total solids, respectively. Operating on a continuous regimen, the addition of 10 mg/L of the bioproduct based on SP led to 45.7% lower disposal for 50 days. In all cases, no loss of efficiency in the Chemical Oxygen Demand (COD removal was observed.

Multi-spectral and thermodynamic analysis of the interaction mechanism between Cu2+ and α-amylase and impact on sludge hydrolysis.

Science.gov (United States)

Zhou, Ruiqi; Liu, Hong; Hou, Guangying; Ju, Lei; Liu, Chunguang

2017-04-01

An increasing amount of heavy metals (e.g., Cu 2+ ) is being discharged into sewage treatment plants and is accumulating in sludge, which is toxic to the enzyme in sludge or soil when the sludge is used as fertilizer, resulting in unfavorable effect on the biological treatment of sludge and the circulation and conversion of materials in soil. In this research, effect of Cu 2+ on sludge hydrolysis by α-amylase is studied from the respect of concentration and components of soluble organic matter in sludge, using three-dimensional fluorescence spectra. Results show that Cu 2+ exposure not only inhibits the hydrolysis of sludge due to the denaturation of α-amylase but also affects the components of soluble organic matter in sludge. In order to illuminate the interaction mechanism between Cu 2+ and α-amylase (a model of hydrolase in sludge), multi-spectra and isothermal titration microcalorimetry techniques are applied. Results show that the secondary structure of α-amylase is changed as that the α-helical content increases and the structure loosens. The microenvironment of amino acid residue in α-amylase is changed that the hydrophobicity decreases and the polarity increases with Cu 2+ exposure. Isothermal titration calorimetry results show that Van der Waals force and hydrogen bond exist in the interaction between Cu 2+ and α-amylase. Results from this research would favor the development of advanced process for the biological treatment of sludge containing heavy metals.

Activated sludge filterability improvement by nitrifying bacteria abundance regulation in an adsorption membrane bioreactor (Ad-MBR).

Science.gov (United States)

Sun, Fei-Yun; Lv, Xiao-Mei; Li, Ji; Peng, Zhong-Yi; Li, Pu; Shao, Ming-Fei

2014-10-01

Autotrophic nitrifying bacteria have its intrinsic properties including low EPS production, dense colonial structure and slow-growth rate, favoring the sludge filterability improvement. An adsorption-MBR (Ad-MBR) was developed to enrich nitrifier abundance in the MBR chamber by inlet C/N regulation, and its possible positive effect on sludge filterability and underlying mechanisms were investigated. By DNA extraction, PCR amplification and Illumina high-throughput pyrosequencing, the abundance of nitrifying bacteria was accurately quantified. More than 8.29% nitrifier abundance was achieved in Ad-MBR sludge, which was above three times of that in conventional MBR. Regulated C/N ratio and thereafter nitrifier abundance enrichment improved sludge filterability by altering sludge mixture and its supernatant properties, reflected by a good sludge settleability, a low supernatant viscosity and turbidity, a low supernatant organic substances concentration, and a small amount of strong hydrophobic fractional components, thus to profoundly improve sludge filterability and decelerate membrane fouling. Copyright © 2014 Elsevier Ltd. All rights reserved.

Nuclear safety of extended sludge processing on tank 42 and 51 sludge (DWPF sludge feed batch one)

International Nuclear Information System (INIS)

Clemons, J.S.

1993-01-01

The sludge in tanks 42 and 51 is to be washed with inhibited water to remove soluble salts and combined in tank 51 in preparation for feed to DWPF. Since these tanks contain uranium and plutonium, the process of washing must be evaluated to ensure subcriticality is maintained. When the sludge is washed, inhibited water is added, the tank contents are slurried and allowed to settle. The sludge wash water is then decanted to the evaporator feed tank where it is fed to the evaporator to reduce the volume. The resulting evaporator concentrate is sent to a salt tank where it cools and forms crystallized salt cake. This salt cake will later be dissolved, processed in ITP and sent to Z-Area. This report evaluates the supernate and sludge during washing, the impact on the evaporator during concentration of decanted wash water, and the salt tank where the concentrated supernate is deposited. The conclusions generated in this report are specific to the sludge currently contained in tanks 42 and 51

Fractional, biodegradable and spectral characteristics of extracted and fractionated sludge extracellular polymeric substances.

Science.gov (United States)

Wei, Liang-Liang; Wang, Kun; Zhao, Qing-Liang; Jiang, Jun-Qiu; Kong, Xiang-Juan; Lee, Duu-Jong

2012-09-15

Correlation between fractional, biodegradable and spectral characteristics of sludge extracellular polymeric substances (EPS) by different protocols has not been well established. This work extracted sludge EPS using alkaline extractants (NH₄OH and formaldehyde + NaOH) and physical protocols (ultrasonication, heating at 80 °C or cation exchange resin (CER)) and then fractionated the extracts using XAD-8/XAD-4 resins. The alkaline extractants yielded more sludge EPS than the physical protocols. However, the physical protocols extracted principally the hydrophilic components which were readily biodegradable by microorganisms. The alkaline extractants dissolved additional humic-like substances from sludge solids which were refractory in nature. Different extraction protocols preferably extracted EPS with distinct fractional, biodegradable and spectral characteristics which could be applied in specific usages. Copyright © 2012 Elsevier Ltd. All rights reserved.

Vitrification as an alternative to landfilling of tannery sewage sludge

International Nuclear Information System (INIS)

Celary, Piotr; Sobik-Szołtysek, Jolanta

2014-01-01

Highlights: • The possibility of vitrification of tannery sewage sludge was investigated. • Glass cullet was substituted with different wastes of mineral character. • Component ratio in the processed mixtures was optimized. • Environmental safety of the acquired vitrificates was verified. • An alternative management approach of usually landfilled waste was presented. - Abstract: Due to high content of heavy metals such as chromium, tannery sewage sludge is a material which is difficult to be biologically treated as it is in the case of organic waste. Consequently, a common practice in managing tannery sewage sludge is landfilling. This poses a potential threat to both soil and water environments and it additionally generates costs of construction of landfills that meet specific environment protection requirements. Vitrification of this kind of sewage sludge with the addition of mineral wastes can represent an alternative to landfilling. The aim of this study was to investigate the possibility of obtaining an environmentally safe product by means of vitrification of tannery sewage sludge from a flotation wastewater treatment process and chemical precipitation in order to address the upcoming issue of dealing with sewage sludge from the tannery industry which will be prohibited to be landfilled in Poland after 2016. The focus was set on determining mixtures of tannery sewage sludge with additives which would result in the lowest possible heavy metal leaching levels and highest hardness rating of the products obtained from their vitrification. The plasma vitrification process was carried out for mixtures with various amounts of additives depending on the type of sewage sludge used. Only the materials of waste character were used as additives. One finding of the study was an optimum content of mineral additives in vitrified mixture of 30% v/v waste molding sands with 20% v/v carbonate flotation waste from the zinc and lead industry for the formulations with

Vitrification as an alternative to landfilling of tannery sewage sludge

Energy Technology Data Exchange (ETDEWEB)

Celary, Piotr, E-mail: pcelary@is.pcz.czest.pl; Sobik-Szołtysek, Jolanta, E-mail: jszoltysek@is.pcz.czest.pl

2014-12-15

Highlights: • The possibility of vitrification of tannery sewage sludge was investigated. • Glass cullet was substituted with different wastes of mineral character. • Component ratio in the processed mixtures was optimized. • Environmental safety of the acquired vitrificates was verified. • An alternative management approach of usually landfilled waste was presented. - Abstract: Due to high content of heavy metals such as chromium, tannery sewage sludge is a material which is difficult to be biologically treated as it is in the case of organic waste. Consequently, a common practice in managing tannery sewage sludge is landfilling. This poses a potential threat to both soil and water environments and it additionally generates costs of construction of landfills that meet specific environment protection requirements. Vitrification of this kind of sewage sludge with the addition of mineral wastes can represent an alternative to landfilling. The aim of this study was to investigate the possibility of obtaining an environmentally safe product by means of vitrification of tannery sewage sludge from a flotation wastewater treatment process and chemical precipitation in order to address the upcoming issue of dealing with sewage sludge from the tannery industry which will be prohibited to be landfilled in Poland after 2016. The focus was set on determining mixtures of tannery sewage sludge with additives which would result in the lowest possible heavy metal leaching levels and highest hardness rating of the products obtained from their vitrification. The plasma vitrification process was carried out for mixtures with various amounts of additives depending on the type of sewage sludge used. Only the materials of waste character were used as additives. One finding of the study was an optimum content of mineral additives in vitrified mixture of 30% v/v waste molding sands with 20% v/v carbonate flotation waste from the zinc and lead industry for the formulations with

SLUDGE MASS REDUCTION: PRIMARY COMPOSITIONAL FACTORS THAT INFLUENCE MELT RATE FOR FUTURE SLUDGE BATCH PROJECTIONS

International Nuclear Information System (INIS)

Newell, J; Miller, D; Stone, M; Pickenheim, B

2008-01-01

The Savannah River National Laboratory (SRNL) was tasked to provide an assessment of the downstream impacts to the Defense Waste Processing Facility (DWPF) of decisions regarding the implementation of Al-dissolution to support sludge mass reduction and processing. Based on future sludge batch compositional projections from the Liquid Waste Organization's (LWO) sludge batch plan, assessments have been made with respect to the ability to maintain comparable projected operating windows for sludges with and without Al-dissolution. As part of that previous assessment, candidate frits were identified to provide insight into melt rate for average sludge batches representing with and without Al-dissolution flowsheets. Initial melt rate studies using the melt rate furnace (MRF) were performed using five frits each for Cluster 2 and Cluster 4 compositions representing average without and with Al-dissolution. It was determined, however, that the REDOX endpoint (Fe 2+ /ΣFe for the glass) for Clusters 2 and 4 resulted in an overly oxidized feed which negatively affected the initial melt rate tests. After the sludge was adjusted to a more reduced state, additional testing was performed with frits that contained both high and low concentrations of sodium and boron oxides. These frits were selected strictly based on the ability to ascertain compositional trends in melt rate and did not necessarily apply to any acceptability criteria for DWPF processing. The melt rate data are in general agreement with historical trends observed at SRNL and during processing of SB3 (Sludge Batch 3)and SB4 in DWPF. When MAR acceptability criteria were applied, Frit 510 was seen to have the highest melt rate at 0.67 in/hr for Cluster 2 (without Al-dissolution), which is compositionally similar to SB4. For Cluster 4 (with Al-dissolution), which is compositionally similar to SB3, Frit 418 had the highest melt rate at 0.63 in/hr. Based on this data, there appears to be a slight advantage of the Frit

Utilization of municipal sewage sludge as additives for the production of eco-cement

International Nuclear Information System (INIS)

Lin, Yiming; Zhou, Shaoqi; Li, Fuzhen; Lin, Yixiao

2012-01-01

Highlights: ► The results of X-ray diffraction (XRD) pattern and scanning electron micrograph (SEM) indicated that the major components in the eco-cement clinkers were similar to those in ordinary Portland cement. ► Though the C 2 S phase formation increased with the increase of sewage sludge contents. ► All the eco-cement pastes had a longer initial setting time and final setting time than those of plain cement paste, which increased as the sewage sludge contents in raw meal increased. ► All the eco-cement pastes had lower early flexural strengths and it increased with the increase of sewage sludge contents increased, while the compressive strengths decreased slightly. ► However, it had no significant effect on all the strengths at later ages. - Abstract: The effects of using dried sewage sludge as additive on cement property in the process of clinker burning were investigated in this paper. The eco-cement samples were prepared by adding 0.50–15.0% of dried sewage sludge to unit raw meal, and then the mixtures were burned at 1450 °C for 2 h. The results indicated that the major components in the eco-cement clinkers were similar to those in ordinary Portland cement. Although the C 2 S phase formation increased with the increase of sewage sludge content, it was also found that the microstructure of the mixture containing 15.0% sewage sludge in raw meal was significantly different and that a larger amount of pores were distributed in the clinker. Moreover, all the eco-cement pastes had a longer initial setting time and final setting time than those of plain cement paste, which increased as the sewage sludge content in the raw meal increased. All the eco-cement pastes had lower early flexural strengths, which increased as the sewage sludge content increased, while the compressive strengths decreased slightly. However, this had no significant effect on all the strengths at later stages. Furthermore, the leaching concentrations of all the types of eco

Sludge busters

Energy Technology Data Exchange (ETDEWEB)

Pichon, Max

2010-07-15

Full text: A few years ago, For Earth developed low energy sub-surface aeration systems to increase the biological activity in the wastewater sludge ponds. Then came the idea to introduce probiotic bacteria to really ramp up the process, which promises massive time and cost savings in sludge management. Increasing the volumes of specific bacteria reactivates the sludge, accelerating biological nutrient removal in general and, by tailoring the bacteria, targeting specific organic waste types. The technology is already running at more than 30 councils across NSW and in some commercial settings, such as dairy farms. Shane McKibbin, GM of For Earth, said the 'Probiotic, Low Energy Aeration System' offers considerable upside. “The cost savings have been enormous with some councils, including the work done at Woolgoolga Water Reclamation Plant at Coffs Harbour,” he said. Sludge settling in wastewater treatment plant lagoons is typically pumped out, centrifuged to remove water and then landfilled. In Woolgoolga's case that process was costing Coffs Harbour Water $150 a cubic metre; McKibbin said they've slashed that to a measly $5 a cubic metre. An array of 'industrial air stones' is dropped 1m below the surface to create an oxygenated blanket across the surface, overcoming the tendency of sludge ponds to stagnate. The key though is floating probiotic dosing lines across the surface, which kick-starts the probiotics process. “Previously, some operators just wanted to throw it on with a bucket, so the bacteria would get thrown into one corner of the pond. But since we introduced the dosing system it has really improved the overall performance,” said McKibbin.The dosing pump system automatically applies the bacteria into the dosing line according to a specified program, ensuring the probiotics are spread out across the pond and across the week. “I would say it improves and accelerates the result by 30 per cent,” he adds. “The biggest problem was that

Sludge busters

International Nuclear Information System (INIS)

Pichon, Max

2010-01-01

Full text: A few years ago, For Earth developed low energy sub-surface aeration systems to increase the biological activity in the wastewater sludge ponds. Then came the idea to introduce probiotic bacteria to really ramp up the process, which promises massive time and cost savings in sludge management. Increasing the volumes of specific bacteria reactivates the sludge, accelerating biological nutrient removal in general and, by tailoring the bacteria, targeting specific organic waste types. The technology is already running at more than 30 councils across NSW and in some commercial settings, such as dairy farms. Shane McKibbin, GM of For Earth, said the 'Probiotic, Low Energy Aeration System' offers considerable upside. “The cost savings have been enormous with some councils, including the work done at Woolgoolga Water Reclamation Plant at Coffs Harbour,” he said. Sludge settling in wastewater treatment plant lagoons is typically pumped out, centrifuged to remove water and then landfilled. In Woolgoolga's case that process was costing Coffs Harbour Water $150 a cubic metre; McKibbin said they've slashed that to a measly $5 a cubic metre. An array of 'industrial air stones' is dropped 1m below the surface to create an oxygenated blanket across the surface, overcoming the tendency of sludge ponds to stagnate. The key though is floating probiotic dosing lines across the surface, which kick-starts the probiotics process. “Previously, some operators just wanted to throw it on with a bucket, so the bacteria would get thrown into one corner of the pond. But since we introduced the dosing system it has really improved the overall performance,” said McKibbin.The dosing pump system automatically applies the bacteria into the dosing line according to a specified program, ensuring the probiotics are spread out across the pond and across the week. “I would say it improves and accelerates the result by 30 per cent,” he adds. “The biggest problem was that

Sludge Stabilization Campaign blend plan

International Nuclear Information System (INIS)

De Vries, M.L.

1994-01-01

This sludge stabilization blend plan documents the material to be processed and the order of processing for the FY95 Sludge Stabilization Campaign. The primary mission of this process is to reduce the inventory of unstable plutonium bearing sludge. The source of the sludge is residual and glovebox floor sweepings from the production of material at the Plutonium Finishing Plant (PFP). The reactive sludge is currently being stored in various gloveboxes at PFP. There are two types of the plutonium bearing material that will be thermally stabilized in the muffle furnace: Plutonium Reclamation Facility (PRF) sludge and Remote Mechanical C (RMC) Line material

Analysis of sludge from Hanford K East Basin canisters

Energy Technology Data Exchange (ETDEWEB)

Makenas, B.J. [ed.] [comp.] [DE and S Hanford, Inc., Richland, WA (United States); Welsh, T.L. [B and W Protec, Inc. (United States); Baker, R.B. [DE and S Hanford, Inc., Richland, WA (United States); Hoppe, E.W.; Schmidt, A.J.; Abrefah, J.; Tingey, J.M.; Bredt, P.R.; Golcar, G.R. [Pacific Northwest National Lab., Richland, WA (United States)

1997-09-12

Sludge samples from the canisters in the Hanford K East Basin fuel storage pool have been retrieved and analyzed. Both chemical and physical properties have been determined. The results are to be used to determine the disposition of the bulk of the sludge and to assess the impact of residual sludge on dry storage of the associated intact metallic uranium fuel elements. This report is a summary and review of the data provided by various laboratories. Although raw chemistry data were originally reported on various bases (compositions for as-settled, centrifuged, or dry sludge) this report places all of the data on a common comparable basis. Data were evaluated for internal consistency and consistency with respect to the governing sample analysis plan. Conclusions applicable to sludge disposition and spent fuel storage are drawn where possible.

Effect of sludge behavior on performance of centrifugal contactor

Energy Technology Data Exchange (ETDEWEB)

Sakamoto, A.; Sano, Y.; Takeuchi, M. [Japan Atomic Energy Agency - JAEA, 4-33 Muramatsu Tokai-mura Naka-gun Ibaraki-pref. 319-1194 (Japan)

2016-07-01

The Japan Atomic Energy Agency has been developing an annular centrifugal contactor for solvent extraction in spent fuel reprocessing, which allows the mixing of aqueous and organic phases in the annular area and their separation from the mixed phase in the rotor. The effects of sludge behavior on the performance of a centrifugal contactor were investigated. Sludge accumulation during the operation of the centrifugal contactor was observed only in the rotor. Based on the sludge accumulation behavior, the effects of rotor sludge accumulation on the performance of phase separation and extraction were investigated using several types of rotors, which simulated different sludge accumulation levels in the separation area. It was confirmed that rotor sludge accumulation would affect the phase separation performance but not the extraction performance. This can be explained by the structure of the centrifugal contactor, wherein the extraction reaction and phase separation mainly proceed in the housing and rotor, respectively.

Gas composition of sludge residue profiles in a sludge treatment reed bed between loadings.

Science.gov (United States)

Larsen, Julie D; Nielsen, Steen M; Scheutz, Charlotte

2017-11-01

Treatment of sludge in sludge treatment reed bed systems includes dewatering and mineralization. The mineralization process, which is driven by microorganisms, produces different gas species as by-products. The pore space composition of the gas species provides useful information on the biological processes occurring in the sludge residue. In this study, we measured the change in composition of gas species in the pore space at different depth levels in vertical sludge residue profiles during a resting period of 32 days. The gas composition of the pore space in the sludge residue changed during the resting period. As the resting period proceeded, atmospheric air re-entered the pore space at all depth levels. The methane (CH 4 ) concentration was at its highest during the first part of the resting period, and then declined as the sludge residue became more dewatered and thereby aerated. In the pore space, the concentration of CH 4 often exceeded the concentration of carbon dioxide (CO 2 ). However, the total emission of CO 2 from the surface of the sludge residue exceeded the total emission of CH 4 , suggesting that CO 2 was mainly produced in the layer of newly applied sludge and/or that CO 2 was emitted from the sludge residue more readily compared to CH 4 .

Sludge recovery apparatus

International Nuclear Information System (INIS)

Marmo, A.R.

1979-01-01

An improved design of a sludge recovery apparatus used in the fabrication of nuclear fuel is described. This apparatus provides for automatic separation of sludge from the grinder coolant, drying of the sludge into a flowable powder and transfer of the dry powder to a salvage container. It can be constructed to comply with criticality-safe-geometry requirements and to obviate need for operating personnel in its immediate vicinity. (UK)

Combustion of Sewage Sludge as Alternative Fuel for Cement Industry

Institute of Scientific and Technical Information of China (English)

LI Fuzhou; ZHANG Wei

2011-01-01

The combustion of sewage sludge and coal was studied by thermogravimetric analysis.Both differential scanning calorimetric analysis and derivative thermogravimetric profiles showed differences between combustion of sewage sludge and coal, and non-isothermal kinetics analysis method was applied to evaluate the combustion process. Based on Coats-Redfem integral method, some reaction models were tested,the mechanism and kinetics of the combustion reaction were discussed. The results show that the combustion of sewage sludge is mainly in the Iow temperature stage, meanwhile the ignition temperature and Arrhenius activation energy are lower than that of coal. The combustion of sewage sludge has the advantage over coal in some aspects, thus sewage sludge can partly replace coal used as cement industry fuel.

Gas composition of sludge residue profiles in a sludge treatment reed bed between loadings

DEFF Research Database (Denmark)

Larsen, Julie Dam; Nielsen, Steen M; Scheutz, Charlotte

2017-01-01

Treatment of sludge in sludge treatment reed bed systems includes dewatering and mineralization. The mineralization process, which is driven by microorganisms, produces different gas species as by-products. The pore space composition of the gas species provides useful information on the biological...... processes occurring in the sludge residue. In this study, we measured the change in composition of gas species in the pore space at different depth levels in vertical sludge residue profiles during a resting period of 32 days. The gas composition of the pore space in the sludge residue changed during...

Sludge technology assessment

International Nuclear Information System (INIS)

Krause, T.R.; Cunnane, J.C.; Helt, J.E.

1994-12-01

The retrieval, processing, and generation of final waste forms from radioactive tank waste sludges present some of the most challenging technical problems confronting scientists and engineers responsible for the waste management programs at the various Department of Energy laboratories and production facilities. Currently, the Department of Energy is developing a strategy to retrieve, process, and generate a final waste form for the sludge that meets the acceptance criteria for the final disposition. An integral part of this strategy will be use of separation processes that treat the sludge; the goal is to meet feed criteria for the various processes that will generate the final waste form, such as vitrification or grouting. This document is intended to (1) identify separation technologies which are being considered for sludge treatment at various DOE sites, (2) define the current state of sludge treatment technology, (3) identify what research and development is required, (4) identify current research programs within either DOE or academia developing sludge treatment technology, and (5) identify commercial separation technologies which may be applicable. Due to the limited scope of this document, technical evaluations regarding the need for a particular separations technology, the current state of development, or the research required for implementation, are not provided

Effects of sewage sludge on the yield of plants in the rotation system of wheat-white head cabbage-tomato

Directory of Open Access Journals (Sweden)

Mehmet Arif Özyazıcı

2013-01-01

Full Text Available This research was carried to determine the effects of sewage sludge applications on the yield and yield components of plants under crop rotation system. The field experiments were conducted in the Bafra Plain, located in the north region of Turkey. In this research, the “wheat-white head cabbage-tomato” crop rotation systems have been examined and the same crop rotation has been repeated in two separate years and field trials have been established. Seven treatments were compared: a control without application of sludge nor nitrogen fertilization, a treatment without sludge, but nitrogen and phosphorus fertilization, applied at before sowing of wheat and five treatments where, respectively 10, 20, 30, 40 and 50 tons sludge ha-1. The experimental design was a randomized complete block with three replications. The results showed that all the yield components of wheat and yield of white head cabbage and tomato increased significantly with increasing rates of sewage sludge as compared to control. As a result, 20 t ha-1 of sewage sludge application could be recommended the suitable dose for the rotation of wheat-white head cabbage-tomato in soil and climatic conditions of Bafra Plain.

Enhanced selection of micro-aerobic pentachlorophenol degrading granular sludge

Energy Technology Data Exchange (ETDEWEB)

Lv, Yuancai, E-mail: donkey1204@hotmail.com [State Key Laboratory of Pulp and Paper Engineering, College of Light Industry and Food Science, South China University of Technology, Guangzhou 510640 (China); Chen, Yuancai, E-mail: chenyc@scut.edu.cn [State Key Laboratory of Pulp and Paper Engineering, College of Light Industry and Food Science, South China University of Technology, Guangzhou 510640 (China); Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, College of Environment and Energy, South China University of Technology, Guangzhou 510006 (China); Song, Wenzhe, E-mail: songwenzhe007@126.com [Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, College of Environment and Energy, South China University of Technology, Guangzhou 510006 (China); Hu, Yongyou, E-mail: ppyyhu@scut.edu.cn [State Key Laboratory of Pulp and Paper Engineering, College of Light Industry and Food Science, South China University of Technology, Guangzhou 510640 (China); Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, College of Environment and Energy, South China University of Technology, Guangzhou 510006 (China)

2014-09-15

Graphical abstract: In this work, an aerobic column reactor was placed before the USB to maintain micro-oxygen condition in the reactor and the micro-aerobic pentachlorophenol (PCP) degrading granular sludge under oxygen-limited conditions (0.1–0.2 mg L{sup −1}) was successfully obtained. PCP degradation by the micro-aerobic system was studied and the variance of microbial community was also discussed by using PCR-DGGE analysis. - Highlights: • Micro-aerobic granular sludge was cultivated in column-type combined reactors. • PCP biodegradation, VFA accumulation and biogas production were studied. • The function of Methanogenic archaeon in the system was investigated. • Fluctuation and diversity of microbial community were discussed by DGGE analysis. • The dominated microorganisms were identified by 16S rDNA sequences. - Abstract: Column-type combined reactors were designed to cultivate micro-aerobic pentachlorophenol (PCP) degrading granular sludge under oxygen-limited conditions (0.1–0.2 mg L{sup −1}) over 39-day experimental period. Micro-aerobic granular had both anaerobic activity (SMA: 2.34 mMCH{sub 4}/h g VSS) and aerobic activity (SOUR: 2.21 mMO{sub 2}/h g VSS). Metabolite analysis results revealed that PCP was sequentially dechlorinated to TCP, DCP, and eventually to MCP. Methanogens were not directly involved in the dechlorination of PCP, but might played a vital role in stabilizing the overall structure of the granule sludge. For Eubacteria, the Shannon Index (2.09 in inoculated granular sludge) increased both in micro-aerobic granular sludge (2.61) and PCP-degradation granular sludge (2.55). However, for Archaea, it decreased from 2.53 to 1.85 and 1.84, respectively. Although the Shannon Index demonstrated slight difference between micro-aerobic granular sludge and PCP-degradation granular sludge, the Principal Component Analysis (PCA) indicated obvious variance of the microbial composition, revealing significant effect of micro

Enhanced selection of micro-aerobic pentachlorophenol degrading granular sludge

International Nuclear Information System (INIS)

Lv, Yuancai; Chen, Yuancai; Song, Wenzhe; Hu, Yongyou

2014-01-01

Graphical abstract: In this work, an aerobic column reactor was placed before the USB to maintain micro-oxygen condition in the reactor and the micro-aerobic pentachlorophenol (PCP) degrading granular sludge under oxygen-limited conditions (0.1–0.2 mg L −1 ) was successfully obtained. PCP degradation by the micro-aerobic system was studied and the variance of microbial community was also discussed by using PCR-DGGE analysis. - Highlights: • Micro-aerobic granular sludge was cultivated in column-type combined reactors. • PCP biodegradation, VFA accumulation and biogas production were studied. • The function of Methanogenic archaeon in the system was investigated. • Fluctuation and diversity of microbial community were discussed by DGGE analysis. • The dominated microorganisms were identified by 16S rDNA sequences. - Abstract: Column-type combined reactors were designed to cultivate micro-aerobic pentachlorophenol (PCP) degrading granular sludge under oxygen-limited conditions (0.1–0.2 mg L −1 ) over 39-day experimental period. Micro-aerobic granular had both anaerobic activity (SMA: 2.34 mMCH 4 /h g VSS) and aerobic activity (SOUR: 2.21 mMO 2 /h g VSS). Metabolite analysis results revealed that PCP was sequentially dechlorinated to TCP, DCP, and eventually to MCP. Methanogens were not directly involved in the dechlorination of PCP, but might played a vital role in stabilizing the overall structure of the granule sludge. For Eubacteria, the Shannon Index (2.09 in inoculated granular sludge) increased both in micro-aerobic granular sludge (2.61) and PCP-degradation granular sludge (2.55). However, for Archaea, it decreased from 2.53 to 1.85 and 1.84, respectively. Although the Shannon Index demonstrated slight difference between micro-aerobic granular sludge and PCP-degradation granular sludge, the Principal Component Analysis (PCA) indicated obvious variance of the microbial composition, revealing significant effect of micro-aerobic condition and

Activated sludge model No. 3

DEFF Research Database (Denmark)

Gujer, W.; Henze, M.; Mino, T.

1999-01-01

The Activated Sludge Model No. 3 (ASM3) can predict oxygen consumption, sludge production, nitrification and denitrification of activated sludge systems. It relates to the Activated Sludge Model No. 1 (ASM1) and corrects for some defects of ASM I. In addition to ASM1, ASM3 includes storage of org...

SLUDGE WASHING AND DEMONSTRATION OF THE DWPF FLOWSHEET IN THE SRNL SHIELDED CELLS FOR SLUDGE BATCH 7A QUALIFICATION

Energy Technology Data Exchange (ETDEWEB)

Pareizs, J.; Billings, A.; Click, D.

2011-07-08

Waste Solidification Engineering (WSE) has requested that characterization and a radioactive demonstration of the next batch of sludge slurry (Sludge Batch 7a*) be completed in the Shielded Cells Facility of the Savannah River National Laboratory (SRNL) via a Technical Task Request (TTR). This characterization and demonstration, or sludge batch qualification process, is required prior to transfer of the sludge from Tank 51 to the Defense Waste Processing Facility (DWPF) feed tank (Tank 40). The current WSE practice is to prepare sludge batches in Tank 51 by transferring sludge from other tanks. Discharges of nuclear materials from H Canyon are often added to Tank 51 during sludge batch preparation. The sludge is washed and transferred to Tank 40, the current DWPF feed tank. Prior to transfer of Tank 51 to Tank 40, SRNL simulates the Tank Farm and DWPF processes with a Tank 51 sample (referred to as the qualification sample). Sludge Batch 7a (SB7a) is composed of portions of Tanks 4, 7, and 12; the Sludge Batch 6 heel in Tank 51; and a plutonium stream from H Canyon. SRNL received the Tank 51 qualification sample (sample ID HTF-51-10-125) following sludge additions to Tank 51. This report documents: (1) The washing (addition of water to dilute the sludge supernate) and concentration (decanting of supernate) of the SB7a - Tank 51 qualification sample to adjust sodium content and weight percent insoluble solids to Tank Farm projections. (2) The performance of a DWPF Chemical Process Cell (CPC) simulation using the washed Tank 51 sample. The simulation included a Sludge Receipt and Adjustment Tank (SRAT) cycle, where acid was added to the sludge to destroy nitrite and reduce mercury, and a Slurry Mix Evaporator (SME) cycle, where glass frit was added to the sludge in preparation for vitrification. The SME cycle also included replication of five canister decontamination additions and concentrations. Processing parameters were based on work with a non

Efficiency of a pilot-scale integrated sludge thickening and digestion reactor in treating low-organic excess sludge.

Science.gov (United States)

He, Qiang; Li, Jiang; Liu, Hongxia; Tang, Chuandong; de Koning, Jaap; Spanjers, Henri

2012-06-01

The sludge production from medium- and small-scale wastewater treatment plants in the Three Gorges Reservoir Region is low and non-stable; especially, the organic content in this sludge is low (near 40% of VS/TS). An integrated thickening and digestion (ISTD) reactor was developed to treat this low-organic excess sludge. After a flow test and start-up experiment of the reactor, a running experiment was used to investigate the excess sludge treatment efficiency under five different excess sludge inflows: 200, 300, 400, 500 and 400 L/d (a mixture of excess sludge and primary sludge in a volume ratio of 9:1). This trial was carried out in the wastewater treatment plant in Chongqing, which covers 80% of the Three Gorges Reservoir Region, under the following conditions: (1) sludge was heated to 38-40 degrees C using an electrical heater to maintain anaerobic mesophilic digestion; (2) the biogas produced was recirculated to mix raw sludge with anaerobic sludge in the reactor under the flow rate of 12.5 L/min. There were three main results. Firstly, the flow pattern of the inner reactor was almost completely mixed under the air flow of 12.0 L/min using clear water. Secondly, under all the different sludge inflows, the water content in the outlet sludge was below 93%. Thirdly, the organic content in the outlet sludge was decreased from 37% to 30% and from 24% to 20%, whose removal ratio was in relation to the organic content of the inlet sludge. The excess sludge treatment capacity of the ISTD reactor was according to the organic content in the excess sludge.

Effect of sonically induced deflocculation on the efficiency of ozone mediated partial sludge disintegration for improved production of biogas.

Science.gov (United States)

Sowmya Packyam, G; Kavitha, S; Adish Kumar, S; Kaliappan, S; Yeom, Ick Tae; Rajesh Banu, J

2015-09-01

In this study, ultrasonication was used for sludge deflocculation, followed by cell disintegration using ozone. The effect of this phase separated sono-ozone pretreatment is evaluated based on extra polymeric substances release, deoxyribonucleic acid (DNA) in the medium, solubilization of intra cellular components and suspended solids (SS) reduction. Ultrasonically induced deflocculation was optimized at an energy dosage of 76.4(log 1.88)kJ/kg TS. During cell disintegration (ozone dosage 0.0011 mgO3/mgSS), chemical oxygen demand solubilization (COD) and SS reduction of sonic mediated ozone pretreated sludge were 25.4% and 17.8% comparatively higher than ozone pretreated sludge, respectively. Further, biogas production potential of control (raw), flocculated (ozone pretreated), and deflocculated (sonic mediated ozone pretreated) sludges were observed to be 0.202, 0.535 and 0.637 L/(gVS), respectively. Thus, the phase separated pretreatment at lower ultrasonic specific energy and low dose ozone proved to enhance the anaerobic biodegradability efficiently. Copyright © 2015 Elsevier B.V. All rights reserved.

Bacterial composition of activated sludge - importance for floc and sludge properties

Energy Technology Data Exchange (ETDEWEB)

Nielsen, Per H.; Thomsen, Trine R.; Nielsen, Jeppe L.

2003-07-01

Activated sludge flocs consist of numerous constituents which, together with other factors, are responsible for floc structure and floc properties. These properties largely determine the sludge properties such as flocculation, settling and dewaterability. In this paper we briefly review the present knowledge about the role of bacteria in relation to floc and sludge properties, and we present a new approach to investigate the identity and function of the bacteria in the activated sludge flocs. The approach includes identification of the important bacteria and a characterization of their physiological and functional properties. It is carried out by use of culture-independent molecular biological methods linked with other methods to study the physiology and function maintaining a single cell resolution. Using this approach it was found that floc-forming properties differed among the various bacterial groups, e.g. that different microcolony-forming bacteria had very different sensitivities to shear and that some of them deflocculated under anaerobic conditions. in our opinion, the approach to combine identity with functional analysis of the dominant bacteria in activated sludge by in situ methods is a very promising way to investigate correlations between presence of specific bacteria, and floc and sludge properties that are of interest. (author)

Radiation hygienization of raw sewage sludge

International Nuclear Information System (INIS)

Shah, M.R.; Lavale, D.S.; Rawat, P.; Benny, P.G.; Sharma, A.K.; Dey, G.R.; Bhave, V.

2001-01-01

'Radiation treatment of municipal sewage sludge can achieve resource conservation and recovery objectives. The liquid sludge irradiator of Sludge Hygienization Research Irradiator at Baroda (India) was operated for generating data on treatment of raw sludge containing 3-4 % solids. The plant system was modified for irradiating raw sludge without affecting basic irradiator initially designed to treat digested sludge. Hourly samples were analysed for estimation of disinfection dose requirement. Sand separated from the sludge was used as in-situ dosimeter by making use of its thermoluminescence property. Investigations are being carried out for regrowth of Total Coliforms in the sludge samples from this irradiator. Possibility of inadequate treatment due to geometric configuration of irradiator is being checked. (author)

Effects of additives on solidification of API separator sludge.

Science.gov (United States)

Faschan, A; Tittlebaum, M; Cartledge, F; Eaton, H

1991-08-01

API separator sludge was solidified with various combinations of binders and absorbent soil additives. The binders utilized were Type I Portland Cement, Type C Flyash, and a 1:1 combination of the two. The soil additives used were bentonite, diatomite, Fuller's earth, and two brands of chemically altered bentonites, or organoclays. The effectiveness of the solidification materials was based on their effect on the physical and leaching characteristics of the sludge.It was determined the Portland cement and combination binders provided the sludge with adequate physical and strength characteristics. It was also determined the affinity of each additive for water had an important influence on the physical characteristics of the solidified sludge. The results of the leaching procedure indicated the binders alone reduced the leachability of organic constituents from the sludge by 1/5 to 1/10. It appeared the use of the additives with the binders may have further reduced the leachability of constituents from sludge, with the incorporation of the organoclay additives further reducing leachability by up to 1/2. Also, it appeared the absorbing capacity of the additives was directly related to their ability to reduce the leachability of organic constituents from the sludge.

Fiscal year 1994 1/25-scale sludge mobilization testing

International Nuclear Information System (INIS)

Powell, M.R.; Gates, C.M.; Hymas, C.R.; Sprecher, M.A.; Morter, N.J.

1995-07-01

There are 28 one-million-gallon double-shell radioactive waste tanks on the Hanford Reservation in southeastern Washington State. The waste in these tanks was generated during processing of nuclear materials. Solids-laden slurries were placed into many of the tanks. Over time, the waste solids have settled to form a layer of sludge in the bottom of these tanks. The sludge layer thickness varies from tank to tank with some having only a few centimeters or no sludge up to some tanks which have about 4.5 m (15 ft) of sludge. It is planned that the waste will be removed from these tanks as part of the overall Hanford site cleanup efforts. Jet mixer pumps are to be placed into the tanks to stir up (mobilize) the sludge and form a uniform slurry suitable for pumping to downstream processing facilities. These mixer pumps use powerful jets of tank fluid directed horizontally out of two, diametrically opposed nozzles near the tank bottom. These fluid jets impinge upon the sludge and stir it up. The amount of sludge mobilized by the mixer pump jets depends not only on the jet properties, but also on the ability of the sludge to resist the jets. It is the goal of the work described in this document to develop the ability to predict how much sludge will be mobilized by the mixer pumps based on the size and velocity of the mixer pump jets and the physical and chemical properties of the tank sludge

Fertilization value of municipal sewage sludge for Eucalyptus camaldulensis plants

Directory of Open Access Journals (Sweden)

Soudani Leila

2017-03-01

Full Text Available The wastewater treatment produces a large amount of sludge. The different uses of eliminations sludge such as landfills or incineration have consequences negative for the environment, the agricultural use has increased worldwide, especially in crops and few or no studies have been conducted with forest plantations in Algeria. The objective of this study is to assess fertilizing characteristics of the sludge from the wastewater treatment plant of Tiaret (Algeria. One-year-old saplings of Eucalyptus camaldulensis were transplanted into pots with sludge/soil mixtures where sludge content was 20%, 40% and 60%. Biometric measurements (height, base diameter, diameter at mid-height and the number of leaves were performed during six months after planting. Results demonstrated the positive effect of sludge application. A significant difference in height increment and number of leaves was found between the control and sludge-treated plants. Biometric values for all sludge mixtures were higher than those for control plants (100% soil. The mixture, which contained 60% sludge, gives the best result, except for a diameter of stem. Plants grown on sludge/soil mixture had average height 49.4 ± 24.1 cm and average number of leaves 68.8 ± 6.2 while average height for plants grown on soil was 34.3 ± 12.8 cm and average number of leaves was 40 ± 3.8. Sludge application provides soil amendment and additional nutrient supply for planted trees.

Sewage sludges disinfection

International Nuclear Information System (INIS)

Alexandre, D.; Gevaudan, P.P.

1977-01-01

There is a hygienic risk in using biological sewage sludges for agriculture. Systematic analyses carried out on sludge samples obtained from purification plants in the Eastern and Southern part of France, show the almost uniform presence of pathogenic microorganisms. Some of them survive more than nine months after application to the soil. Conventional processes for disinfection, liming and heat, make the sludge unsuitable for agricultural use. On the other hand, irradiation involves no modification of structure and composition of sludges. Radiation doses required for disinfection vary according to the type of microorganism. Some of them are eliminated at rather low doses (200 krad), but mycobacteria, viruses and eggs of worms resist to more important doses. The security dose is estimated to be approx. 1000 krad

Mitigation of Hydrogen Gas Generation from the Reaction of Uranium Metal with Water in K Basin Sludge and Sludge Waste Forms

Energy Technology Data Exchange (ETDEWEB)

Sinkov, Sergey I.; Delegard, Calvin H.; Schmidt, Andrew J.

2011-06-08

Prior laboratory testing identified sodium nitrate and nitrite to be the most promising agents to minimize hydrogen generation from uranium metal aqueous corrosion in Hanford Site K Basin sludge. Of the two, nitrate was determined to be better because of higher chemical capacity, lower toxicity, more reliable efficacy, and fewer side reactions than nitrite. The present lab tests were run to determine if nitrate’s beneficial effects to lower H2 generation in simulated and genuine sludge continued for simulated sludge mixed with agents to immobilize water to help meet the Waste Isolation Pilot Plant (WIPP) waste acceptance drainable liquid criterion. Tests were run at ~60°C, 80°C, and 95°C using near spherical high-purity uranium metal beads and simulated sludge to emulate uranium-rich KW containerized sludge currently residing in engineered containers KW-210 and KW-220. Immobilization agents tested were Portland cement (PC), a commercial blend of PC with sepiolite clay (Aquaset II H), granulated sepiolite clay (Aquaset II G), and sepiolite clay powder (Aquaset II). In all cases except tests with Aquaset II G, the simulated sludge was mixed intimately with the immobilization agent before testing commenced. For the granulated Aquaset II G clay was added to the top of the settled sludge/solution mixture according to manufacturer application directions. The gas volumes and compositions, uranium metal corrosion mass losses, and nitrite, ammonia, and hydroxide concentrations in the interstitial solutions were measured. Uranium metal corrosion rates were compared with rates forecast from the known uranium metal anoxic water corrosion rate law. The ratios of the forecast to the observed rates were calculated to find the corrosion rate attenuation factors. Hydrogen quantities also were measured and compared with quantities expected based on non-attenuated H2 generation at the full forecast anoxic corrosion rate to arrive at H2 attenuation factors. The uranium metal

Mitigation of Hydrogen Gas Generation from the Reaction of Uranium Metal with Water in K Basin Sludge and Sludge Waste Forms

International Nuclear Information System (INIS)

Sinkov, Sergey I.; Delegard, Calvin H.; Schmidt, Andrew J.

2011-01-01

Prior laboratory testing identified sodium nitrate and nitrite to be the most promising agents to minimize hydrogen generation from uranium metal aqueous corrosion in Hanford Site K Basin sludge. Of the two, nitrate was determined to be better because of higher chemical capacity, lower toxicity, more reliable efficacy, and fewer side reactions than nitrite. The present lab tests were run to determine if nitrate's beneficial effects to lower H2 generation in simulated and genuine sludge continued for simulated sludge mixed with agents to immobilize water to help meet the Waste Isolation Pilot Plant (WIPP) waste acceptance drainable liquid criterion. Tests were run at ∼60 C, 80 C, and 95 C using near spherical high-purity uranium metal beads and simulated sludge to emulate uranium-rich KW containerized sludge currently residing in engineered containers KW-210 and KW-220. Immobilization agents tested were Portland cement (PC), a commercial blend of PC with sepiolite clay (Aquaset II H), granulated sepiolite clay (Aquaset II G), and sepiolite clay powder (Aquaset II). In all cases except tests with Aquaset II G, the simulated sludge was mixed intimately with the immobilization agent before testing commenced. For the granulated Aquaset II G clay was added to the top of the settled sludge/solution mixture according to manufacturer application directions. The gas volumes and compositions, uranium metal corrosion mass losses, and nitrite, ammonia, and hydroxide concentrations in the interstitial solutions were measured. Uranium metal corrosion rates were compared with rates forecast from the known uranium metal anoxic water corrosion rate law. The ratios of the forecast to the observed rates were calculated to find the corrosion rate attenuation factors. Hydrogen quantities also were measured and compared with quantities expected based on non-attenuated H2 generation at the full forecast anoxic corrosion rate to arrive at H2 attenuation factors. The uranium metal

Degradation of slime extracellular polymeric substances and inhibited sludge flocs destruction contribute to sludge dewaterability enhancement during fungal treatment of sludge using filamentous fungus Mucor sp. GY-1.

Science.gov (United States)

Wang, Zhenyu; Zheng, Guanyu; Zhou, Lixiang

2015-09-01

Mechanisms responsible for the sludge dewaterability enhanced by filamentous fungi during fungal treatment of sludge were investigated in the present study. The filamentous fungus Mucor sp. GY-1, isolated from waste activated sludge, enhanced sludge dewaterability by 82.1% to achieve the lowest value of normalized sludge specific resistance to filtration (SRF), 8.18 × 10(10) m · L/kg · g-TSS. During the fungal treatment of sludge, 57.8% of slime extracellular polymeric substances (EPS) and 51.1% of polysaccharide in slime EPS were degraded, respectively, by Mucor sp. GY-1, contributing to the improvement of sludge dewaterability. Slime EPS is much more available for Mucor sp. GY-1 than either LB-EPS or TB-EPS that bound with microbial cells. In addition, filamentous fungus Mucor sp. GY-1 entrapped small sludge particles and inhibited the destruction of sludge flocs larger than 100 μm, thus enhancing sludge dewaterability, during fungal treatment of sludge using Mucor sp. GY-1. Copyright © 2015 Elsevier Ltd. All rights reserved.

Bioremediation of oil sludge contaminated soil using bulking agent mixture enriched consortia of microbial inoculants based by irradiated compost

International Nuclear Information System (INIS)

Tri Retno, D.L.; Mulyana, N.

2013-01-01

Bulking agent mixture enriched consortia of microbial inoculants based by irradiated compost was used on bioremediation of microcosm scale contaminated by hydrocarbon soil. Bioremediation composting was carried out for 42 days. Composting was done with a mixture of bulking agent (sawdust, residual sludge biogas and compost) by 30%, mud petroleum (oil sludge) by 20% and 50% of soil. Mixture of 80% soil and 20% oil sludge was used as a control. Irradiated compost was used as a carrier for consortia of microbial inoculants (F + B) which biodegradable hydrocarbons. Treatment variations include A1, A2, B1, B2, C1, C2, D1 and D2. Process parameters were observed to determine the optimal conditions include: temperature, pH, water content, TPC (Total Plate Count) and degradation of % TPH (Total Petroleum Hydrocarbon). Optimal conditions were achieved in the remediation of oil sludge contamination of 20% using the B2 treatment with the addition consortia of microbial inoculants based by irradiated compost of sawdust (bulking agentby 30% at concentrations of soil by 50% with TPH degradation optimal efficiency of 81.32%. The result of GC-MS analysis showed that bioremediation for 42 days by using a sawdust as a mixture of bulking agents which enriched consortia of microbial inoculants based by irradiated compost is biodegradeable, so initial hydrocarbons with the distribution of the carbon chain C-7 to C-54 into final hydrocarbons with the distribution of carbon chain C-6 to C-8. (author)

CFD analysis of sludge accumulation and hydraulic performance of a waste stabilization pond.

Science.gov (United States)

Alvarado, Andres; Sanchez, Esteban; Durazno, Galo; Vesvikar, Mehul; Nopens, Ingmar

2012-01-01

Sludge management in waste stabilization ponds (WSPs) is essential for safeguarding the system performance. Sludge accumulation patterns in WSPs are strongly influenced by the pond hydrodynamics. CFD modeling was applied to study the relation between velocity profiles and sludge deposition during 10 years of operation of the Ucubamba WSP in Cuenca (Ecuador). One tracer experiment was performed and three sludge accumulation scenarios based on bathymetric surveys were simulated. A residence time distribution (RTD) analysis illustrated the decrease of residence times due to sludge deposition. Sludge accumulation rates were calculated. The influence of flow pattern on the sludge deposition was studied, enabling better planning of future pond operation and desludging.

Production of sludge-incorporated paver blocks for efficient waste management.

Science.gov (United States)

Velumani, P; Senthilkumar, S

2018-06-01

Waste management plays a vital role in the reuse of industry wastes in to useful conversions. The treatment of effluents from the combined textile effluent treatment plant and hypo sludge from the paper industry results in sludge generation, which poses a huge challenge for its disposal. Therefore, an eco-friendly attempt is made to utilize them in the production of paver blocks. Paver blocks are construction units that have vast applications in street roads, walking paths, fuel stations, and so on. In this study, an innovative attempt has been made to manufacture paver blocks incorporating textile effluent treatment plant sludge and hypo sludge, to utilize them in suitable proportions. The effect of adding silica fume and polypropylene fibre in paver blocks has also been studied. Paver blocks containing sludge with different proportions were cast based on the recommendations in Indian Standards (IS) 15658, and the test results were compared with the nominal M20 grade and M30 grade paver blocks. The outcomes of the paver block combinations were studied and found to be an effective utilization of sludge with substantial cement replacement of up to 35%, resulting in effective waste management for specific industries. Presently, paver blocks are construction units that have vast application in street roads and other constructions like walking paths, fuel stations, and so on. Also, paver blocks possess easy maintenance during breakages. Based on this application, an innovative attempt has been made to manufacture paver blocks incorporating textile effluent treatment plant sludge and hypo sludge to utilize them in suitable proportions.

Analysis of aerobic granular sludge formation based on grey system theory.

Science.gov (United States)

Zhang, Cuiya; Zhang, Hanmin

2013-04-01

Based on grey entropy analysis, the relational grade of operational parameters with aerobic granular sludge's granulation indicators was studied. The former consisted of settling time (ST), aeration time (AT), superficial gas velocity (SGV), height/diameter (H/D) ratio and organic loading rates (OLR), the latter included sludge volume index (SVI) and set-up time. The calculated result showed that for SVI and set-up time, the influence orders and the corresponding grey entropy relational grades (GERG) were: SGV (0.9935) > AT (0.9921) > OLR (0.9894) > ST (0.9876) > H/D (0.9857) and SGV (0.9928) > H/D (0.9914) > AT (0.9909) > OLR (0.9897) > ST (0.9878). The chosen parameters were all key impact factors as each GERG was larger than 0.98. SGV played an important role in improving SVI transformation and facilitating the set-up process. The influence of ST on SVI and set-up time was relatively low due to its dual functions. SVI transformation and rapid set-up demanded different optimal H/D ratio scopes (10-20 and 16-20). Meanwhile, different functions could be obtained through adjusting certain factors' scope.

Operational experience at the Sludge Treatment Facility

International Nuclear Information System (INIS)

Sy, D.J.

1987-01-01

The Sludge Treatment Facility (STF) at the Oak Ridge Gaseous Diffusion Plant has been in operation since April 1987. The facility was designed to encapsulate hazardous sludge wastes in a cement matrix. Fixation will allow the waste to meet or exceed applicable compressive strength and leachability requirements. Thus, the grout mixture complies with the Resource Conservation and Recovery Act (RCRA) guidelines as a nonhazardous waste. The grout mixture is based upon a recipe formulation developed after several years of waste stream characterization and formulation studies. The wastes to be treated at the STF are wastes impounded in two ponds. The ponds have a combined capacity of 4.5 million gallons of sludge. The sludge is transferred from the ponds to a 15,000-gallon capacity storage tank by the use of a dredge. The grout mixture recipe dictates the amount of sludge, cement, fly ash, and admixture required for weighing per batch. All ingredients are weighed and then transferred to a tilt or high energy mixer for mixing. The grout mixture is then transferred to 89- or 96-gallon steel drums. The drums are placed in a storage yard designed for a point source discharge from the yard

Production and remediation of low sludge simulated Purex waste glasses, 2: Effects of sludge oxide additions on glass durability

International Nuclear Information System (INIS)

Ramsey, W.G.

1993-01-01

Glass produced during the Purex 4 campaigns of the Integrated DWPF Melter System (IDMS) and the 774 Research Melter contained a lower fraction of sludge components than targeted by the Product Composition Control System (PCCS). Purex 4 glass was more durable than the benchmark (EA) glass, but was less durable than most other simulated SRS high-level waste glasses. Further, the measured durability of Purex 4 glass was not as well correlated with the durability predicted from the DWPF process control algorithm, probably because the algorithm was developed to predict the durability of SRS high-level waste glasses with higher sludge content than Purex 4. A melter run, designated Purex 4 Remediation, was performed using the 774 Research Melter to determine if the initial PCCS target composition determined for Purex 4 would produce acceptable glass whose durability could be accurately modeled by the DWPF glass durability algorithm. Reagent grade oxides and carbonates were added to Purex 4 melter feed stock to simulate a higher sludge loading. Each canister of glass produced was sampled and the glass durability was determined by the Product Consistency Test method. This document details the durability data and subsequent analysis

Reduction of excess sludge production in sequencing batch reactor through incorporation of chlorine dioxide oxidation

International Nuclear Information System (INIS)

Wang Guanghua; Sui Jun; Shen Huishan; Liang Shukun; He Xiangming; Zhang Minju; Xie Yizhong; Li Lingyun; Hu Yongyou

2011-01-01

In this study, chlorine dioxide (ClO 2 ) instead of chlorine (Cl 2 ) was proposed to minimize the formation of chlorine-based by-products and was incorporated into a sequencing batch reactor (SBR) for excess sludge reduction. The results showed that the sludge disintegrability of ClO 2 was excellent. The waste activated sludge at an initial concentration of 15 g MLSS/L was rapidly reduced by 36% using ClO 2 doses of 10 mg ClO 2 /g dry sludge which was much lower than that obtained using Cl 2 based on similar sludge reduction efficiency. Maximum sludge disintegration was achieved at 10 mg ClO 2 /g dry sludge for 40 min. ClO 2 oxidation can be successfully incorporated into a SBR for excess sludge reduction without significantly harming the bioreactor performance. The incorporation of ClO 2 oxidation resulted in a 58% reduction in excess sludge production, and the quality of the effluent was not significantly affected.

Improvement of sludge dewaterability and removal of sludge-borne metals by bioleaching at optimum pH.

Science.gov (United States)

Liu, Fenwu; Zhou, Lixiang; Zhou, Jun; Song, Xingwei; Wang, Dianzhan

2012-06-30

Bio-acidification caused by bio-oxidation of energy substances during bioleaching is widely known to play an important role in improving sludge-borne metals removal. Here we report that bioleaching also drastically enhances sludge dewaterability in a suitable pH level. To obtain the optimum initial concentrations of energy substances and pH values for sludge dewaterability during bioleaching, bio-oxidation of Fe(2+) and S(0) under co-inoculation with Acidithiobacillus thiooxidans TS6 and Acidothiobacillus ferrooxidans LX5 and their effects on sludge dewaterability and metals removal during sludge bioleaching were investigated. Results indicated that the dosage of energy substances with 2g/L S(0) and 2g/L Fe(2+) could obtain bio-oxidation efficiencies of up to 100% for Fe(2+) and 50% for S(0) and were the optimal dosages for sludge bioleaching. The removal efficiencies of sludge-borne Cu and Cr could reach above 85% and 40%, respectively, and capillary suction time (CST) of bioleached sludge decreased to as low as ∼10s from initial 48.9s for fresh sludge when sludge pH declined to ∼2.4 through bioleaching. These results confirm the potential of bioleaching as a novel method for improving sludge dewaterability as well as removal of metals. Copyright © 2012 Elsevier B.V. All rights reserved.

Rheology of Savannah River Site Tank 42 radioactive sludges. Revision 1

International Nuclear Information System (INIS)

Ha, B.C.; Bibler, N.E.

1995-01-01

Knowledge of the rheology of the radioactive sludge slurries at the Savannah River Site (SRS) is necessary in order to ensure that they can be retrieved from waste tanks and processed for final disposal. At Savannah River Site (SRS), Tank 42 sludge represents one of the first HLW radioactive sludges to be vitrified in the Defense Waste Processing Facility (DWPF). The rheological properties of unwashed Tank 42 sludge slurries at various solids concentrations were measured remotely in the Shielded Cells at the Savannah River Technology Center (SRTC) using a modified Haake Rotovisco viscometer. Rheological properties of Tank 42 radioactive sludge were measured as a function of weight percent total solids to ensure that the first DWPF radioactive sludge batch can be pumped and processed in the DWPF with the current design bases. The yield stress and consistency of the sludge slurries were determined by assuming a Bingham plastic fluid model

Applying Sewage Sludge to Eucalyptus grandis Plantations: Effects on Biomass Production and Nutrient Cycling through Litterfall

International Nuclear Information System (INIS)

Da Silva, P.H.M.; Poggiani, F.; Laclau, J.P.

2011-01-01

In most Brazilian cities sewage sludge is dumped into sanitary landfills, even though its use in forest plantations as a fertilizer and soil conditioner might be an interesting option. Sewage sludge applications might reduce the amounts of mineral fertilizers needed to sustain the productivity on infertile tropical soils. However, sewage sludge must be applied with care to crops to avoid soil and water pollution. The aim of our study was to assess the effects of dry and wet sewage sludges on the growth and nutrient cycling of Eucalyptus grandis plantations established on the most common soil type for Brazilian eucalypt plantations. Biomass production and nutrient cycling were studied over a 36-month period in a complete randomized block design. Four experimental treatments were compared: wet sewage sludge, dry sludge, mineral fertilizer, and no fertilizer applications. The two types of sludges as well as mineral fertilizer increased significantly the biomass of Eucalyptus trees. Wood biomass productions 36 months after planting were similar in the sewage sludge and mineral fertilization treatments (about 80 tons ha - '1) and 86 % higher than in the control treatment. Sewage sludge application also affected positively leaf litter production and significantly increased nutrient transfer among the components of the ecosystem.

Applying Sewage Sludge to Eucalyptus grandis Plantations: Effects on Biomass Production and Nutrient Cycling through Litterfall

Directory of Open Access Journals (Sweden)

Paulo Henrique Müller da Silva

2011-01-01

Full Text Available In most Brazilian cities sewage sludge is dumped into sanitary landfills, even though its use in forest plantations as a fertilizer and soil conditioner might be an interesting option. Sewage sludge applications might reduce the amounts of mineral fertilizers needed to sustain the productivity on infertile tropical soils. However, sewage sludge must be applied with care to crops to avoid soil and water pollution. The aim of our study was to assess the effects of dry and wet sewage sludges on the growth and nutrient cycling of Eucalyptus grandis plantations established on the most common soil type for Brazilian eucalypt plantations. Biomass production and nutrient cycling were studied over a 36-month period in a complete randomized block design. Four experimental treatments were compared: wet sewage sludge, dry sludge, mineral fertilizer, and no fertilizer applications. The two types of sludges as well as mineral fertilizer increased significantly the biomass of Eucalyptus trees. Wood biomass productions 36 months after planting were similar in the sewage sludge and mineral fertilization treatments (about 80 tons ha−1 and 86% higher than in the control treatment. Sewage sludge application also affected positively leaf litter production and significantly increased nutrient transfer among the components of the ecosystem.

Diversity, Localization, and Physiological Properties of Filamentous Microbes Belonging to Chloroflexi Subphylum I in Mesophilic and Thermophilic Methanogenic Sludge Granules

Science.gov (United States)

Yamada, Takeshi; Sekiguchi, Yuji; Imachi, Hiroyuki; Kamagata, Yoichi; Ohashi, Akiyoshi; Harada, Hideki

2005-01-01

We previously reported that the thermophilic filamentous anaerobe Anaerolinea thermophila, which is the first cultured representative of subphylum I of the bacterial phylum Chloroflexi, not only was one of the predominant constituents of thermophilic sludge granules but also was a causative agent of filamentous sludge bulking in a thermophilic (55°C) upflow anaerobic sludge blanket (UASB) reactor in which high-strength organic wastewater was treated (Y. Sekiguchi, H. Takahashi, Y. Kamagata, A. Ohashi, and H. Harada, Appl. Environ. Microbiol. 67:5740-5749, 2001). To further elucidate the ecology and function of Anaerolinea-type filamentous microbes in UASB sludge granules, we surveyed the diversity, distribution, and physiological properties of Chloroflexi subphylum I microbes residing in UASB granules. Five different types of mesophilic and thermophilic UASB sludge were used to analyze the Chloroflexi subphylum I populations. 16S rRNA gene cloning-based analyses using a 16S rRNA gene-targeted Chloroflexi-specific PCR primer set revealed that all clonal sequences were affiliated with the Chloroflexi subphylum I group and that a number of different phylotypes were present in each clone library, suggesting the ubiquity and vast genetic diversity of these populations in UASB sludge granules. Subsequent fluorescence in situ hybridization (FISH) of the three different types of mesophilic sludge granules using a Chloroflexi-specific probe suggested that all probe-reactive cells had a filamentous morphology and were widely distributed within the sludge granules. The FISH observations also indicated that the Chloroflexi subphylum I bacteria were not always the predominant populations within mesophilic sludge granules, in contrast to thermophilic sludge granules. We isolated two mesophilic strains and one thermophilic strain belonging to the Chloroflexi subphylum I group. The physiological properties of these isolates suggested that these populations may contribute to the

Ceftriaxone-associated gallbladder sludge. Identification of calcium-ceftriaxone salt as a major component of gallbladder precipitate

International Nuclear Information System (INIS)

Park, H.Z.; Lee, S.P.; Schy, A.L.

1991-01-01

Ceftriaxone, a third-generation cephalosporin, is partially excreted into bile. With its clinical use, the formation of gallbladder sludge detected by ultrasonography has been reported. Four surgical specimens were examined and no gallstones were found. Instead, fine precipitates of 20-250 microns were present. Microscopically, there was a small number of cholesterol monohydrate crystals and bilirubin granules among an abundant amount of granular-crystalline material that was not morphologically cholesterol monohydrate crystals. The chemical composition of the precipitates (n = 4) was determined. There was a small amount of cholesterol (1.7% +/- 0.8%) and bilirubin (13.9% +/- 0.74%). The major component of the precipitate was a residue. On further analysis using thin-layer chromatography, high-performance liquid chromatography, and electron microprobe analysis, the residue was identified as a calcium salt of ceftriaxone. The residue also had identical crystal morphology and chromatographic elution profile as authentic calcium-ceftriaxone standards. It is concluded that ceftriaxone, after excretion and being concentrated in the gallbladder bile, can form a precipitate. The major constituent has been identified as a ceftriaxone-calcium salt

Cost and effectiveness comparisons of various types of sludge irradiation and sludge pasteurization treatments

International Nuclear Information System (INIS)

Morris, M.E.

1976-01-01

The radiation from 137 Cs, a major constituent of nuclear fuel reprocessing waste, can be used to sterilize sewage sludge. This paper compares the effectiveness and cost of heat pasteurization, irradiation, and thermoradiation (simultaneous heating/irradiation), three competing methods of sludge disinfection. The cost of irradiation and thermoradiation is slightly higher than heat pasteurization costs for liquid sludges, although minor changes in oil availability or prices could change this. If the viral destruction could be done easily by other means, a 500-kilorad irradiation dose would be effective and less costly. For dry sewage sludges, irradiation is as effective and much less costly than any of the liquid sludge disinfection processes. Irradiation of compost appears to be cheaper and more practical than any heat pasteurization process for the dry sludge (the insulating property of the compost makes heating difficult). 6 tables, 2 fig

Strategies for characterizing compositions of industrial pulp and paper sludge

Science.gov (United States)

Aslanzadeh, Solmaz; Kemal, Rahmat A.; Pribowo, Amadeus Y.

2018-01-01

The large quantities of waste sludge produced by the pulp and paper industry present significant environmental challenges. In order to minimize the amounts of waste, the pulp sludge should be utilized for productive applications. In order to find feasible solutions, the sludge need to be characterized. In this study, the potential of using acid pretreatment and ashing method to determine the chemical compositions of the sludge is investigated. This study shows that acid pretreatment could be used to dissolve and determine the composition of CaCO3 in the pulp sludge. CaCO3 removal also facilitates the measurement of fiber and ash (clay) contents by using the ashing method. The optimum acid concentration used to completely dissolve CaCO3 was determined using a titration method. Using this method, the measurement of the chemical composition of the sludge sample revealed that it consisted primarily of CaCO3 (55% w/w), clay (25%, w/w), and fibers (18%, w/w). Based on these chemical compositions, potential utilization for the sludge could be determined.

F-Canyon Sludge Physical Properties

International Nuclear Information System (INIS)

Poirier, M. R.; Hansen, P. R.; Fink, S. D.

2005-01-01

The Site Deactivation and Decommissioning (SDD) Organization is evaluating options to disposition the 800 underground tanks (including removal of the sludge heels from these tanks). To support this effort, DandD requested assistance from Savannah River National Laboratory (SRNL) personnel to determine the pertinent physical properties to effectively mobilize the sludge from these tanks (Tanks 804, 808, and 809). SDD provided SRNL with samples of the sludge from Tanks 804, 808, and 809. The authors measured the following physical properties for each tank: particle settling rate, shear strength (i.e., settled solids yield stress), slurry rheology (i.e., yield stress and consistency), total solids concentration in the sludge, soluble solids concentration of the sludge, sludge density, and particle size distribution

The sustainable utilization of malting industry wastewater biological treatment sludge

Science.gov (United States)

Vasilenko, T. A.; Svintsov, A. V.; Chernysh, I. V.

2018-01-01

The article deals with the research of using the sludge from malting industry wastewater’s biological treatment and the calcium carbonate slurry as organo-mineral fertilizing additives. The sludge, generated as a result of industrial wastewater biological treatment, is subject to dumping at solid domestic waste landfills, which has a negative impact on the environment, though its properties and composition allow using it as an organic fertilizer. The physical and chemical properties of both wastes have been studied; the recommendations concerning the optimum composition of soil mix, containing the above-mentioned components, have been provided. The phytotoxic effect on the germination capacity and sprouts of cress (Lepidium sativum), barley (Hordéum vulgáre) and oats (Avena sativa) in soil mixes has been determined. The heavy metals and arsenic contents in the sludge does not exceed the allowable level; it is also free of pathogenic flora and helminthes.

INTEGRATED WASTE WATER TREATMENT ACCOMPANIED BY MINIMAL GENERATION OF EXCESSIVE ACTIVATED SLUDGE OR SEDIMENT

Directory of Open Access Journals (Sweden)

Makisha Nikolay Alekseevich

2012-12-01

ments held. A combination of aerobic and anaerobic processes helps provide the proper quality of integrated biological treatment. Chambers of the aeration reactor are also equipped with the polymer feed of various compositions. Sludge treatment that is also strongly needed was performed by means of aerobic stabilization accompanied by ejecting aeration. The experiment findings demonstrate its substantial effect in terms of both components, including sewage and sludge treatment.

Response surface methodology for the optimization of sludge solubilization by ultrasonic pre-treatment

Science.gov (United States)

Zheng, Mingyue; Zhang, Xiaohui; Lu, Peng; Cao, Qiguang; Yuan, Yuan; Yue, Mingxing; Fu, Yiwei; Wu, Libin

2018-02-01

The present study examines the optimization of the ultrasonic pre-treatment conditions with response surface experimental design in terms of sludge disintegration efficiency (solubilisation of organic components). Ultrasonic pre-treatment for the maximum solubilization with residual sludge enhanced the SCOD release. Optimization of the ultrasonic pre-treatment was conducted through a Box-Behnken design (three variables, a total of 17 experiments) to determine the effects of three independent variables (power, residence time and TS) on COD solubilization of sludge. The optimal COD was obtained at 17349.4mg/L, when the power was 534.67W, the time was 10.77, and TS was 2%, while the SE of this condition was 28792J/kg TS.

Fate of return activated sludge after ozonation: an optimization study for sludge disintegration.

Science.gov (United States)

Demir, Ozlem; Filibeli, Ayse

2012-09-01

The effects of ozonation on sludge disintegration should be investigated before the application of ozone during biological treatment, in order to minimize excess sludge production. In this study, changes in sludge and supernatant after ozonation of return activated sludge were investigated for seven different ozone doses. The optimum ozone dose to avoid inhibition of ozonation and high ozone cost was determined in terms of disintegration degree as 0.05 g O3/gTS. Suspended solid and volatile suspended solid concentrations of sludge decreased by 77.8% and 71.6%, respectively, at the optimum ozone dose. Ozonation significantly decomposed sludge flocs. The release of cell contents was proved by the increase of supernatant total nitrogen (TN) and phosphorus (TP). While TN increased from 7 mg/L to 151 mg/L, TP increased from 8.8 to 33 mg/L at the optimum ozone dose. The dewaterability and filterability characteristics of the ozonated sludge were also examined. Capillary suction time increased with increasing ozone dosage, but specific resistance to filtration increased to a specific value and then decreased dramatically. The particle size distribution changed significantly as a result of floc disruption at an optimum dose of 0.05 gO3/gTS.

Development of substance flow based Life Cycle Assessment tool for sewage sludge treatment and disposal

DEFF Research Database (Denmark)

Yoshida, Hiroko; Clavreul, Julie; Scheutz, Charlotte

Life Cycle Assessment (LCA) is a method to quantify environmental impacts of products or systems. It is often done by correlating material and energy demands with certain input characteristics. An attempt was made to evaluate the robustness of the substance flow based LCA for wastewater and sludg...

Petroleum Sludge as gypsum replacement in cement plants: Its Impact on Cement Strength

Science.gov (United States)

Benlamoudi, Ali; Kadir, Aeslina Abdul; Khodja, Mohamed

2017-08-01

Due to high cost of cement manufacturing and the huge amount of resources exhaustion, companies are trying to incorporate alternative raw materials or by-products into cement production so as to produce alternative sustainable cement. Petroleum sludge is a dangerous waste that poses serious imparts on soil and groundwater. Given that this sludge contains a high percentage of anhydrite (CaSO4), which is the main component of gypsum (CaSO4.2H2O), it may play the same gypsum role in strength development. In this research, a total replacement of gypsum (100%) has been substituted by petroleum sludge in cement production and has led to an increase of 28.8% in UCS values after 28 curing days. Nevertheless, the burning of this waste has emitted a considerable amount of carbon monoxide (CO) gas that needs to be carefully considered prior to use petroleum sludge within cement plants.

Sewage sludge based producer gas of rich H{sub 2} content as a fuel for an IC engine

Energy Technology Data Exchange (ETDEWEB)

Szwaja, Stanislaw; Cupial, Karol [Czestochowa Univ. of Technology (Poland)

2010-07-01

particular focus on engine working cycles repeatability and potential knock onset. Additionally, these two quantities for methane, biogas (consisted of 65% CH{sub 4} and 35% CO{sub 2}) and hydrogen combustion has been also determined. It was conducted for making comparison between these gases and the sludge based producer gas with respect to applying them as fuels for the IC engine. (orig.)

Effects of CeO2 nanoparticles on sludge aggregation and the role of extracellular polymeric substances – Explanation based on extended DLVO

International Nuclear Information System (INIS)

You, Guoxiang; Hou, Jun; Wang, Peifang; Xu, Yi; Wang, Chao; Miao, Lingzhan; Lv, Bowen; Yang, Yangyang; Luo, Hao

2016-01-01

The extended DLVO (XDLVO) theory was applied to elucidate the potential effects of CeO 2 nanoparticles (CeO 2 NPs) on sludge aggregation and the role of extracellular polymeric substances (EPS). In this study, seven different concentrations of CeO 2 NPs were added to activated sludge cultured in sequencing batch reactors (SBRs) and compared with a control test that received no CeO 2 NPs. After exposure to 50 mg/L CeO 2 NPs, a negligible change (p>0.1) occurred in the sludge volume index (SVI), whereas the flocculability and aggregation of the sludge decreased by 18.8% and 11.2%, respectively, resulting in a high effluent turbidity. The XDLVO theory demonstrated that the adverse effects of the CeO 2 NPs on sludge aggregation were due to an enhanced barrier energy. Compared to the van der Waals energies (W A ) and the electric double layer (W R ), the acid-base interaction (W AB ) markedly changed for the various concentrations of CeO 2 NPs. The EPS played a decisive role in the sludge surface characteristics, as the removal of EPS equals to the negative effects induced by 5–10 mg/L CeO 2 NPs on the sludge flocculability and aggregation. The presence of CeO 2 NPs induced negative contributions to the tight boundary EPS (TB-EPS) and core bacteria while positive contributions to the total interaction energy of the loose boundary EPS (LB-EPS). - Highlights: • CeO 2 NPs adversely affected the flocculability and aggregation of the sludge. • The presence of CeO 2 NPs increased the energy barrier and led to a stable suspension. • The removal of EPS equals to the negative effects induced by 5–10 mg/L CeO 2 NPs. • The acid-base interaction was dominate and markedly changed for the CeO 2 NPs. • CeO 2 NPs induced negative contributions to the TB-EPS while positive to the LB-EPS.

Treatment of spent nuclear fuel L-basin sludge

International Nuclear Information System (INIS)

Westover, B.L.; Oji, L.N.; Martin, H.L.; Nichols, D.M.

1997-01-01

Each production reactor at the DOE Savannah River Site (SRS) has a disassembly basin whose primary purpose is to cool irradiated production fuel and target. The disassembly basins also provide a shielded environment for personnel. Material has historically resided in the basins for 6 to 12 months. Increases in basin storage time have occurred, and have caused the buildup of a sludge layer on the basin floors to be greater than historical levels. The sludge is composed primarily of inorganic oxide and hydroxide corrosion products. The sludge layer has increased the turbidity and conductivity of the basin water, contributed to fuel corrosion, and has impacted fuel handling operations. Initial characterization of the sludge indicates that it is a low-level radioactive aqueous waste. This evaluation looked at methods to separate the sludge into its liquid and solid phases. The experimental data obtained during this evaluation clearly shows that a filtration-based approach to dewatering using an Oberlin pressure filtration unit at SRS is possible. This research task was to identify and optimize filtration and settling parameters pursuant sludge processing. The research specifically addressed: choice of filter aid, filter aid to sludge ratio, choice and dosage of polymer flocculation and settling agents, and the determination of Kynch curve settling parameters. Two commercial perlite filter-aids were identified as the most suitable. Of 11 water soluble flocculating polymers evaluated, 3 cationic commercial types formed stable flocs in the screening tests. In low doses, the flocculating polymers also enhanced sludge particle settling and decreased filtrate turbidity. The filtration cake from the sludge can be solidified to meet waste acceptance and storage criteria. However, the conductivity of the remaining filtrate does not meet Reactor Area Return Water criteria and may require a secondary filtration process. 2 refs., 14 figs., 5 tabs

Efficiency of Worm Reactors in Reducing Sludge Volume in Activated Sludge Systems

Directory of Open Access Journals (Sweden)

Azam Naderi

2017-01-01

Full Text Available The activated sludge process is the most widely used on a global scale for the biological treatment of both domestic and industrial effluents. One problem associated with the process, however, is the high volume of sludge produced. Excess sludge treatment and disposal account for up to 60% of the total operating costs of urban wastewater treatment plants due to the stringent environmental regulations on excess sludge disposal. These strict requirements have encouraged a growing interest over the last few years in reducing sludge volumes produced at biological treatment plants and a number of physical, chemical, and mechanical methods have been accordingly developed for this purpose. The proposed methods are disadvantaged due to their rather high investment and operation costs. An alternative technology that avoids many of these limitations is the worm reactor. In this study, the characteristics of this technology are investigated while the related literature is reviewed to derive the optimal conditions for the operation of this process in different situations.

Important operational parameters of membrane bioreactor-sludge disintegration (MBR-SD) system for zero excess sludge production.

Science.gov (United States)

Yoon, Seong-Hoon

2003-04-01

In order to prevent excess sludge production during wastewater treatment, a membrane bioreactor-sludge disintegration (MBR-SD) system has been introduced, where the disintegrated sludge is recycled to the bioreactor as a feed solution. In this study, a mathematical model was developed by incorporating a sludge disintegration term into the conventional activated sludge model and the relationships among the operational parameters were investigated. A new definition of F/M ratio for the MBR-SD system was suggested to evaluate the actual organic loading rate. The actual F/M ratio was expected to be much higher than the apparent F/M ratio in MBR-SD. The kinetic parameters concerning the biodegradability of organics hardly affect the system performance. Instead, sludge solubilization ratio (alpha) in the SD process and particulate hydrolysis rate constant (k(h)) in biological reaction determine the sludge disintegration number (SDN), which is related with the overall economics of the MBR-SD system. Under reasonable alpha and k(h) values, SDN would range between 3 and 5 which means the amount of sludge required to be disintegrated would be 3-5 times higher for preventing a particular amount of sludge production. Finally, normalized sludge disintegration rate (q/V) which is needed to maintain a certain level of MLSS in the MBR-SD system was calculated as a function of F/V ratio.

STUDY ON MAXIMUM SPECIFIC SLUDGE ACIVITY OF DIFFERENT ANAEROBIC GRANULAR SLUDGE BY BATCH TESTS

Institute of Scientific and Technical Information of China (English)

无

2001-01-01

The maximum specific sludge activity of granular sludge from large-scale UASB, IC and Biobed anaerobic reactors were investigated by batch tests. The limitation factors related to maximum specific sludge activity (diffusion, substrate sort, substrate concentration and granular size) were studied. The general principle and procedure for the precise measurement of maximum specific sludge activity were suggested. The potential capacity of loading rate of the IC and Biobed anaerobic reactors were analyzed and compared by use of the batch tests results.

Removal of hydrocarbon from refinery tank bottom sludge employing microbial culture.

Science.gov (United States)

Saikia, Rashmi Rekha; Deka, Suresh

2013-12-01

Accumulation of oily sludge is becoming a serious environmental threat, and there has not been much work reported for the removal of hydrocarbon from refinery tank bottom sludge. Effort has been made in this study to investigate the removal of hydrocarbon from refinery sludge by isolated biosurfactant-producing Pseudomonas aeruginosa RS29 strain and explore the biosurfactant for its composition and stability. Laboratory investigation was carried out with this strain to observe its efficacy of removing hydrocarbon from refinery sludge employing whole bacterial culture and culture supernatant to various concentrations of sand-sludge mixture. Removal of hydrocarbon was recorded after 20 days. Analysis of the produced biosurfactant was carried out to get the idea about its stability and composition. The strain could remove up to 85 ± 3 and 55 ± 4.5 % of hydrocarbon from refinery sludge when whole bacterial culture and culture supernatant were used, respectively. Maximum surface tension reduction (26.3 mN m(-1)) was achieved with the strain in just 24 h of time. Emulsification index (E24) was recorded as 100 and 80 % with crude oil and n-hexadecane, respectively. The biosurfactant was confirmed as rhamnolipid containing C8 and C10 fatty acid components and having more mono-rhamnolipid congeners than the di-rhamnolipid ones. The biosurfactant was stable up to 121 °C, pH 2-10, and up to a salinity value of 2-10 % w/v. To our knowledge, this is the first report showing the potentiality of a native strain from the northeast region of India for the efficient removal of hydrocarbon from refinery sludge.

241-Z-361 Sludge Characterization Sampling and Analysis Plan

Energy Technology Data Exchange (ETDEWEB)

BANNING, D.L.

1999-08-05

This sampling and analysis plan (SAP) identifies the type, quantity, and quality of data needed to support characterization of the sludge that remains in Tank 241-2-361. The procedures described in this SAP are based on the results of the 241-2-361 Sludge Characterization Data Quality Objectives (DQO) (BWHC 1999) process for the tank. The primary objectives of this project are to evaluate the contents of Tank 241-2-361 in order to resolve safety and safeguards issues and to assess alternatives for sludge removal and disposal.

241-Z-361 Sludge Characterization Sampling and Analysis Plan

Energy Technology Data Exchange (ETDEWEB)

BANNING, D.L.

1999-07-29

This sampling and analysis plan (SAP) identifies the type, quantity, and quality of data needed to support characterization of the sludge that remains in Tank 241-2-361. The procedures described in this SAP are based on the results of the 241-2-361 Sludge Characterization Data Quality Objectives (DQO) (BWHC 1999) process for the tank. The primary objectives of this project are to evaluate the contents of Tank 241-2-361 in order to resolve safety and safeguards issues and to assess alternatives for sludge removal and disposal.

Reduction of excess sludge production in sequencing batch reactor through incorporation of chlorine dioxide oxidation

Energy Technology Data Exchange (ETDEWEB)

Wang Guanghua [Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration area, College of Environmental Science and Engineering, South China University of Technology, Guangzhou, 510006 (China); Guangzhou municipal engineering design and research institute, Guangzhou, 510060 (China); Sui Jun [Guangzhou municipal engineering design and research institute, Guangzhou, 510060 (China); Shen Huishan; Liang Shukun [Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration area, College of Environmental Science and Engineering, South China University of Technology, Guangzhou, 510006 (China); He Xiangming; Zhang Minju; Xie Yizhong; Li Lingyun [Nanhai Limited Liability Development Company, Foshan, 528200 (China); Hu Yongyou, E-mail: ppyyhu@scut.edu.cn [Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration area, College of Environmental Science and Engineering, South China University of Technology, Guangzhou, 510006 (China) and State Key Lab of Pulp and Paper Engineering, College of Light Industry and Food Science, South China University of Technology; Guangzhou, 510640 (China)

2011-08-15

In this study, chlorine dioxide (ClO{sub 2}) instead of chlorine (Cl{sub 2}) was proposed to minimize the formation of chlorine-based by-products and was incorporated into a sequencing batch reactor (SBR) for excess sludge reduction. The results showed that the sludge disintegrability of ClO{sub 2} was excellent. The waste activated sludge at an initial concentration of 15 g MLSS/L was rapidly reduced by 36% using ClO{sub 2} doses of 10 mg ClO{sub 2}/g dry sludge which was much lower than that obtained using Cl{sub 2} based on similar sludge reduction efficiency. Maximum sludge disintegration was achieved at 10 mg ClO{sub 2}/g dry sludge for 40 min. ClO{sub 2} oxidation can be successfully incorporated into a SBR for excess sludge reduction without significantly harming the bioreactor performance. The incorporation of ClO{sub 2} oxidation resulted in a 58% reduction in excess sludge production, and the quality of the effluent was not significantly affected.

Impedance spectroscopy evolution upon sintering of Al-rich anodising sludge-based extruded bodies

Directory of Open Access Journals (Sweden)

Ribeiro, M. J.

2006-08-01

Full Text Available Alumina based ceramic materials, containing Al-rich sludge as the major component, were processed by extrusion. The sludge derived from the wastewater treatment of aluminium anodising industrial process. Long rods were produced using a vacuum screw extruder, by a careful control of all relevant processing parameters. Then, thick discs were obtained by cutting dried selected rods, to be tested as probes for sintering-dependent electrical properties. The sintering process was followed by performing common dilatometric/thermal analyses but the evolution of electrical conductivity, estimated by impedance spectroscopy (IS, was also used for this purpose. Results show that sintering-dependent morphological evolution up to 1300ºC strongly affects the electrical behaviour of samples, and as a consequence IS seems to be a useful technique to follow the firing process.

Los materiales cerámicos basados en alúmina, conteniendo barros ricos en Al como componente mayoritario fueron procesados por extrusión. Los barros empleados provienen de tratamientos de lavado de residuos de un proceso industrial de anodizado de aluminio. Se produjeron varillas empleando un extrusor de tornillo en vacío con control de todos los parámetros relevantes del proceso. A partir de varillas seleccionadas, se obtuvieron por corte en seco discos cerámicos para evaluar la dependencia de la sinterización y las propiedades eléctricas. El proceso de sinterización se siguió mediante ensayos dilatométricos y análisis térmicos, junto con la evolución de la conductividad eléctrica mediante espectroscopia de impedancia. Los resultados mostraron la evolución de la sinterización y la dependencia morfológica hasta 1300ºC, que afecta fuertemente a la respuesta eléctrica y como consecuencia la espectroscopia de impedancia parece ser una técnica útil en el seguimiento de los procesos de cocción.

Composting of sewage sludge irradiated

International Nuclear Information System (INIS)

Hashimoto, Shoji; Watanabe, Hiromasa; Nishimura, Koichi; Kawakami, Waichiro

1981-01-01

Recently, the development of the techniques to return sewage sludge to forests and farm lands has been actively made, but it is necessary to assure its hygienic condition lest the sludge is contaminated by pathogenic bacteria. The research to treat sewage sludge by irradiation and utilize it as fertilizer or soil-improving material has been carried out from early on in Europe and America. The effects of the irradiation of sludge are sterilization, to kill parasites and their eggs, the inactivation of weed seeds and the improvement of dehydration. In Japan, agriculture is carried out in the vicinity of cities, therefore it is not realistic to use irradiated sludge for farm lands as it is. The composting treatment of sludge by aerobic fermentation is noticed to eliminate the harms when the sludge is returned to forests and farm lands. It is desirable to treat sludge as quickly as possible from the standpoint of sewage treatment, accordingly, the speed of composting is a problem. The isothermal fermentation experiment on irradiated sludge was carried out using a small-scale fermentation tank and strictly controlling fermentation conditions, and the effects of various factors on the fermentation speed were studied. The experimental setup and method are described. The speed of composting reached the maximum at 50 deg C and at neutral or weak alkaline pH. The speed increased with the increase of irradiation dose up to 30 Mrad. (Kako, I.)

Stabilization/solidification of sewage sludge

Energy Technology Data Exchange (ETDEWEB)

Boura, Panagiota; Katsioti, Margarita; Tsakiridis, Petros; Katsiri, Alexandra

2003-07-01

The main objective of this work is to investigate a viable alternative for the final disposal of sewage sludge from urban wastewater treatment plants by its use as an additive in developing new construction materials. For this purpose, several mixtures of sludge- cement and sludge-cement and jarosite/alunite precipitate were prepared. Jarosite/alunite precipitate is a waste product of a new hydrometallurgical process. Two kinds of sludge were used: primary sludge from Psyttalia Wastewater Treatment Plant, which receives a considerable amount of industrial waste, and biological sludge from Metamorphosi Wastewater Treatment Plant. Various percentages of these sludges were stabilized/solidified with Portland cement and Portland cement with jarosite/alunite. The specimens were tested by determination of compressive strength according to the methods described by European Standard EN 196. X-Ray Diffraction (XRD) analysis as well as Thermogravimetry-Differential Thermal Analysis (TG-DTA) were used to determine the hydration products in 28 days. Furthermore, Toxicity Characteristic Leaching Procedure test for heavy metals (TCLP), were carried out in order to investigate the environmental compatibility of these new materials. (author)

K Basin sludge dissolution engineering study

International Nuclear Information System (INIS)

Westra, A.G.

1998-01-01

The purpose of this engineering study is to investigate the available technology related to dissolution of the K Basin sludge in nitric acid. The conclusion of this study along with laboratory and hot cell tests with actual sludge samples will provide the basis for beginning conceptual design of the sludge dissolver. The K Basin sludge contains uranium oxides, fragments of metallic U, and some U hydride as well as ferric oxyhydroxide, aluminum oxides and hydroxides, windblown sand that infiltrated the basin enclosure, ion exchange resin, and miscellaneous materials. The decision has been made to dispose of this sludge separate from the fuel elements stored in the basins. The sludge will be conditioned so that it meets Tank Waste Remediation System waste acceptance criteria and can be sent to one of the underground storage tanks. Sludge conditioning will be done by dissolving the fuel constituents in nitric acid, separating the insoluble material, adding neutron absorbers for criticality safety, and then reacting the solution with caustic to co-precipitate the uranium and plutonium. There will be five distinct feed streams to the sludge conditioning process two from the K East (KE) Basin and three from the K West (KW) Basin. The composition of the floor and pit sludges which contain more iron oxides and sand than uranium is much different than the canister sludges which are composed of mostly uranium oxides. The sludge conditioning equipment will be designed to process all of the sludge streams, but some of the operating parameters will be adjusted as necessary to handle the different sludge stream compositions. The volume of chemical additions and the amount of undissolved solids will be much different for floor and pit sludge than for canister sludge. Dissolution of uranium metal and uranium dioxide has been studied quite thoroughly and much information is available. Both uranium metal and uranium dioxide have been dissolved on a large scale in nuclear fuel

Biological treatment of sludge digester liquids.

Science.gov (United States)

van Loosdrecht, M C M; Salem, S

2006-01-01

Nitrogen removal in side stream processes offers a good potential for upgrading wastewater treatment plants (WWTPs) that need to meet stricter effluent standards. Removing nutrients from these internal process flows significantly reduces the N-load to the main treatment plant. These internal flows mainly result from the sludge processing and have a high temperature and a high concentration of ammonia. Therefore, the required reactor volumes as well as the required aerobic SRT are small. Generally, biological treatment processes are more economical and preferred over physical-chemical processes. Recently, several biological treatment processes have been introduced for sludge water treatment. These processes are available now on the activated sludge market (e.g. SHARON, ANAMMOX and BABE processes). The technologies differ in concept and in the limitations guiding the application of these processes for upgrading WWTPs. This paper reviews and compares different biological alternatives for nitrogen removal in side streams. The limitations for selecting a technology from the available ones in the activated sludge market are noted and analysed. It is stressed that the choice for a certain process is based on more aspects than pure process engineering arguments.

Performance indicators and indices of sludge management in urban wastewater treatment plants.

Science.gov (United States)

Silva, C; Saldanha Matos, J; Rosa, M J

2016-12-15

Sludge (or biosolids) management is highly complex and has a significant cost associated with the biosolids disposal, as well as with the energy and flocculant consumption in the sludge processing units. The sludge management performance indicators (PIs) and indices (PXs) are thus core measures of the performance assessment system developed for urban wastewater treatment plants (WWTPs). The key PIs proposed cover the sludge unit production and dry solids concentration (DS), disposal/beneficial use, quality compliance for agricultural use and costs, whereas the complementary PIs assess the plant reliability and the chemical reagents' use. A key PI was also developed for assessing the phosphorus reclamation, namely through the beneficial use of the biosolids and the reclaimed water in agriculture. The results of a field study with 17 Portuguese urban WWTPs in a 5-year period were used to derive the PI reference values which are neither inherent to the PI formulation nor literature-based. Clusters by sludge type (primary, activated, trickling filter and mixed sludge) and by digestion and dewatering processes were analysed and the reference values for sludge production and dry solids were proposed for two clusters: activated sludge or biofilter WWTPs with primary sedimentation, sludge anaerobic digestion and centrifuge dewatering; activated sludge WWTPs without primary sedimentation and anaerobic digestion and with centrifuge dewatering. The key PXs are computed for the DS after each processing unit and the complementary PXs for the energy consumption and the operating conditions DS-determining. The PX reference values are treatment specific and literature based. The PI and PX system was applied to a WWTP and the results demonstrate that it diagnosis the situation and indicates opportunities and measures for improving the WWTP performance in sludge management. Copyright © 2016 Elsevier Ltd. All rights reserved.

Potential investigation of Reusing Ardabil Municipal Wastewater Treatment Plant Sludge Based on AHP and TOPSIS Models

Directory of Open Access Journals (Sweden)

Bizhan Maghsoudlou Kamali

2013-07-01

Full Text Available Introduction :By ever-increasing of population, shortage of water resources and the necessity of wastewater treatment, huge volumes of sludge that is a byproduct of wastewater treatment, requires to be disposed in environmentally secure ways. The target of specifying strategic preferences of reuse of sludge has been to find the correct way of disposal or beneficial use of sludge. Material and methods: In this study, to select the best alternative for reuse of wastewater sludge two systematic methods are introduced, which four alternatives for reuse of sludge (use in agriculture, use in green space, biogas, desert combat are introduced and they are compared by four main parameters including: 1- physicochemical 2-biological 3 - economic, social and cultural, and 4 - environmental pollution situation, that each contains some criteria. In this study, first each of the related parameters and criteria are compared by the expert groups of and through questionnaire. Then these weights are entered into Expert Choice software for the analyze of AHP model and paired comparisons and weightings have been done on the related parameters and criteria. Ultimately, the output of the software is entered into TOPSIS software for the analyze of TOPSIS model until the best alternative is selected. Results: sludge of Ardabil municipal wastewater treatment plant, according to standards and EPA regulations is eligible to class B, and due to the chemical in terms of heavy metals have special (excellent quality and contains considerable quantities of organic substance, nutrients and micronutrients which indicates the fertilizer value of the sludge. Conclusion: The result of this comparison has shown that the application of sludge in green spaces is the most appropriate alternative and then use in agriculture, biogas alternative, and desert combat alternative are, respectively, placed in the second to fourth preference for the reuse of sludge derived from municipal

Experimental continuous sludge microwave system to enhance dehydration ability and hydrogen production from anaerobic digestion of sludge.

Science.gov (United States)

Zhou, Cuihong; Huang, Xintong; Zeng, Meng

2018-05-01

Dehydrating large amounts of sludge produced by sewage treatment plants is difficult. Microwave pretreatment can effectively and significantly improve the dewaterability and hydrogen production of sludge subjected to anaerobic digestion. The aim of this study was to investigate the effects of different microwave conditions on hydrogen production from anaerobic digestion and dewaterability of sludge. Based on an analysis of the electric field distribution, a spiral reactor was designed and a continuous microwave system was built to conduct intermittent and continuous experiments under different conditions. Settling Volume, Capillary Suction Time, particle size, and moisture content of the sludge were measured. The results show that sludge pretreatment in continuous experiments has equally remarkable dehydration performance as in intermittent experiments; the minimum moisture content was 77.29% in the intermittent experiment under a microwave power of 300W and an exposure time of 60sec, and that in the continuous experiment was 77.56% under a microwave power of 400W and an exposure time of 60sec. The peak measured by Differential Scanning Calorimeter appeared earliest under a microwave power of 600W and an exposure time of 180sec. The heat flux at the peak was 4.343W/g, which is relatively small. This indicates that microwave pretreatment induced desirable effects. The maximum yield of hydrogen production was 7.967% under the conditions of microwave power of 500W, exposure time of 120sec, and water bath at 55°C. This research provides a theoretical and experimental basis for the development of a continuous microwave sludge-conditioning system. Copyright © 2017. Published by Elsevier B.V.

Utilization of irradiated sludge for fish feed

International Nuclear Information System (INIS)

Harsojo; Syamsu, Suwirma; Subagyo, Lydia Andini

1994-01-01

An experiment was conducted to study the use of irradiated sludge pellet for fish feed, namely pellet A consisting of irradiated sludge and shrimp waste (1:3); pellet B consisting of irradiated sludge and commercial pellet (1:2). Pellet C, which is a commercial fish feed, was used as control. Catfish (Clarias gariepinus) was used in this experiment. The feed pellet with a dose of 5% of total body weight was given 3 times per day. The results of the experiments showed that based on food conversion for the relative growth of the catfishes, and heavy metal content, pellet A was the best. No contamination of Salmonella or Shigella bacteria was detected in each pellet. (author). 8 refs, 3 tabs, 1 fig

The effect of operational conditions on the sludge specific methanogenic activity and sludge biodegradability

International Nuclear Information System (INIS)

Leitao, R. C.; Santaella, S. T.; Haandel, A. C. van; Zeeman, G.; Lettinga, G.

2009-01-01

The Specific Methanogenic Activity (SMA) and sludge biodegradability of an anaerobic sludge depends on various operational and environmental conditions imposed to the anaerobic reactor. However, the effects of hydraulic retention time (HRT), influent COD concentration (COD i nf) and sludge retention time (SRT) on those two parameters need to be elucidated. This knowledge about SMA can provide insights about the capacity of the UASB reactors to withstand organic and hydraulic shock loads, whereas the biodegradability gives information necessary for final disposal of the sludge. (Author)

The effect of operational conditions on the sludge specific methanogenic activity and sludge biodegradability

Energy Technology Data Exchange (ETDEWEB)

Leitao, R. C.; Santaella, S. T.; Haandel, A. C. van; Zeeman, G.; Lettinga, G.

2009-07-01

The Specific Methanogenic Activity (SMA) and sludge biodegradability of an anaerobic sludge depends on various operational and environmental conditions imposed to the anaerobic reactor. However, the effects of hydraulic retention time (HRT), influent COD concentration (COD{sub i}nf) and sludge retention time (SRT) on those two parameters need to be elucidated. This knowledge about SMA can provide insights about the capacity of the UASB reactors to withstand organic and hydraulic shock loads, whereas the biodegradability gives information necessary for final disposal of the sludge. (Author)

Utilisation of drinking water treatment sludge for the manufacturing of ceramic products

Science.gov (United States)

Kizinievič, O.; Kizinievič, V.

2017-10-01

The influence of the additive of drinking water treatment sludge on the physical and mechanical properties, structural parameters, microstructure of the ceramic products is analysed in the research. Drinking water treatment sludge is renewable, environmentally-friendly, economical additive saving expensive natural raw materials when introduced into the ceramic products. The main drinking water treatment sludge component is amorphous Fe2O3 (70%). Formation masses are prepared by incorporating from 5 % to 60 % of drinking water treatment additive and by burning out at the temperature 1000 °C. Investigation showed that the physical and mechanical properties, microstructure of the ceramic bodies vary depending on the amount of drinking water treatment additive incorporated. In addition, drinking water treatment additive affects the ceramic body as a pigment that dyes the ceramic body in darker red colour.

Co-digestion of cultivated microalgae and sewage sludge from municipal waste water treatment.

Science.gov (United States)

Olsson, Jesper; Feng, Xin Mei; Ascue, Johnny; Gentili, Francesco G; Shabiimam, M A; Nehrenheim, Emma; Thorin, Eva

2014-11-01

In this study two wet microalgae cultures and one dried microalgae culture were co-digested in different proportions with sewage sludge in mesophilic and thermophilic conditions. The aim was to evaluate if the co-digestion could lead to an increased efficiency of methane production compared to digestion of sewage sludge alone. The results showed that co-digestion with both wet and dried microalgae, in certain proportions, increased the biochemical methane potential (BMP) compared with digestion of sewage sludge alone in mesophilic conditions. The BMP was significantly higher than the calculated BMP in many of the mixtures. This synergetic effect was statistically significant in a mixture containing 63% (w/w VS based) undigested sewage sludge and 37% (w/w VS based) wet algae slurry, which produced 23% more methane than observed with undigested sewage sludge alone. The trend was that thermophilic co-digestion of microalgae and undigested sewage sludge did not give the same synergy. Copyright © 2014 Elsevier Ltd. All rights reserved.

Electron beam disinfection of sewage sludge

International Nuclear Information System (INIS)

Hashimoto, Shoji

1992-01-01

Electron beam treatment of dehydrated sewage sludge for safe reutilization was performed. Ranges of total bacterial counts and total coliforms in the sludge were from 1.5 x 10 8 to 1.6 x 10 9 and from 2.2 x 10 7 to 1.5 x 10 8 per wet gram, respectively. Total bacterial counts decreased about 5 log cycles after irradiating 5 kGy and irradiation with 2 kGy was enough to kill all coliforms in sewage sludge. The survival curves of total bacteria, obtained by irradiation in oxygen atmosphere, approached to that in nitrogen atmosphere with the increase of sludge thickness. No effects of dose rate and electron energy were found when the sludge layers were thin enough. Continuous disinfection of sewage sludge cake, with the maximum feed rate of 300 kg-sludge/hr, was successfully performed with a Cockcroft-Walton type electron accelerator, a sludge pump and a flat nozzle. (J.P.N.)

Considerations in the public acceptance of sewage sludge irradiation systems

International Nuclear Information System (INIS)

Dix, G.P.

1975-01-01

Considerations associated with public acceptance of municipal sewage sludge irradiation systems are discussed including the benefit to society, public information and safeguards. Public acceptance of products is based upon the benefit to society as measured by reduced consumer costs, minimization of public risk and enhancement of the quality of life and the environment. When viewed in this positive light, the sludge irradiator has high potential benefits to the community. If large-scale engineering experiments show that sludge irradiation is more cost-effective than other methods, reduced consumer costs would result. Today many sewage plants do not consistently remove pathogens from sludge; sludge irradiation could be an effective method of pathogen removal and result in avoidance of a major public risk. The sludge irradiator may be able to clean up recreational areas, reduce noxious odours from sewage treatment facilities, and reduce the energy requirements for producing fertilizer and soil conditioners and conserve their mineral content. Plant safeguards must be explained to dispel public concern that the contents of the source can be released to the sludge accidentally. This will be the main issue within the technical sector of the public, and the design, procedural and administrative safeguards of the plant must be fully explained. The primary risk associated with sludge irradiators will be the remote possibility of source leakage into the sludge. The various safeguards in sludge irradiation plants are discussed in detail including the form of the radionuclide, encapsulation, the irradiation chamber, safeguards instrumentation, shielding and thermal safeguards. (Author)

Dewatering properties of differently treated sewage sludge

International Nuclear Information System (INIS)

Zehnder, H.J.

1977-01-01

A study on dewatering properties of radiosterilized sewage sludge of different type and origin was carried out. For comparison, also heat-treated (pasteurized) sludge was investigated. The specific filtration resistance of irradiated sewage sludge was lowered in all types of sludge examined. In general, pasteurization increased this parameter. The settling properties of irradiated digested sewage sludge was slightly improved, mainly in the first hours after treatment. Microbial effects may mask the real sedimentation relations especcially in aerobically stabilized sludges. A pasteurization treatment of sewage sludge caused an increased content of soluble substances and suspended particles in the supernatant water. The supernatant water from irradiated sludge showed a smaller increase

Rheology of sludge-slurry grouts

International Nuclear Information System (INIS)

McDaniel, E.W.

1980-10-01

A series of rheograms was developed that relates the critical velocity (velocity where flow changes from laminar to turbulent) of a cementitious grout that incorporates a suspended sludge-slurry to the critical velocity of a reference grout made with a simulated waste solution. The sludge that is now in the Gunite waste tanks at the Oak Ridge National Laboratory (ORNL) will be suspended and pumped to the new waste storage tanks in Melton Valley. The sludge will then be blended with a cement mix base to form a grout which will be injected underground by the shale fracturing process. This report describes the materials, equipment, and techniques used in the laboratory studies to suspend sludges and mix sludge-slurry grouts that have flow properties similar to those of current shale fracturing grouts. Bentonite clay is an effective suspender in dilute NaNO 3 solutions; 15 wt % solids can be suspended with 2.0 wt % bentonite in a 0.1 M NaNO 3 solution. Other suspending materials were evaluated, but bentonite gave the best results. If a slurry grout becomes too viscous to pump, methods must be available to thin the mixture. A number of thinners, friction reducers, and plasticizers were examined. Q-Broxin, a thinner supplied by Baroid, reduced the velocity of a grout required for turbulent flow in a 5.0-cm (2-in.)-diam tube from 1.76 to 1.20 m/s (5.79 to 3.95 ft/s); FX-32C, a plasticizer supplied by Fox Industries, Inc., reduced the velocity from 1.76 to 0.75 m/s

Composting of gamma-radiation disinfected sewage sludge

International Nuclear Information System (INIS)

Kawakami, W.; Hashimoto, S.; Watanabe, H.; Nishimura, K.; Watanabe, H.; Ito, H.; Takehisa, M.

1981-01-01

The composting of radiation disinfected sewage sludge has been studied since 1978, aiming to present a new process of sludge composting for agricultural uses. This process is composed of two steps: irradiation step to disinfect sludge, and composting step to remove odor and easily decomposable organics in sludge. In this paper, the gamma-irradiation effect on sludge cake and composting condition of irradiated sludge are discussed. (author)

Enhanced composting of radiation disinfected sewage sludge

International Nuclear Information System (INIS)

Kawakami, W.; Hashimoto, S.

1984-01-01

Studies on isothermal composting of radiation disinfected sewage sludge and liquid chromatography of water extracts of the products were carried out. The optimum temperature and pH were around 50 deg C and 7 to 8, respectively. The repeated use of products as seeds increased the rate of CO 2 evolution. The rate reached a maximum within 10 hours and decreased rapidly, and the CO 2 evolution ceased after about 3 days. The conversion of organic carbon to carbon dioxide attained to about 40% for the repeated use of products as seeds at the optimum conditions. As long as seeds as available were used, no remarkable difference was found in the composting of unirradiated and irradiated sludges. The composting process using radiation, however, can be carried out at the optimum conditions and is expected to shorten the composting period, because it is not necessary to keep fermentation temperature higher to reduce pathogen in sludge. Liquid chromatographic studies of the products showed that low molecular components decreased and higher molecular ones increased with fermentation. An index expressing the degree of reduction of easily decomposable organics was presented. The index also showed that the optimum temperature for fermentation was 50 deg C. (author)

Ultrasonic sludge pretreatment under pressure.

Science.gov (United States)

Le, Ngoc Tuan; Julcour-Lebigue, Carine; Delmas, Henri

2013-09-01

The objective of this work was to optimize the ultrasound (US) pretreatment of sludge. Three types of sewage sludge were examined: mixed, secondary and secondary after partial methanisation ("digested" sludge). Thereby, several main process parameters were varied separately or simultaneously: stirrer speed, total solid content of sludge (TS), thermal operating conditions (adiabatic vs. isothermal), ultrasonic power input (PUS), specific energy input (ES), and for the first time external pressure. This parametric study was mainly performed for the mixed sludge. Five different TS concentrations of sludge (12-36 g/L) were tested for different values of ES (7000-75,000 kJ/kgTS) and 28 g/L was found as the optimum value according to the solubilized chemical oxygen demand in the liquid phase (SCOD). PUS of 75-150 W was investigated under controlled temperature and the "high power input - short duration" procedure was the most effective at a given ES. The temperature increase in adiabatic US application significantly improved SCOD compared to isothermal conditions. With PUS of 150 W, the effect of external pressure was investigated in the range of 1-16 bar under isothermal and adiabatic conditions for two types of sludge: an optimum pressure of about 2 bar was found regardless of temperature conditions and ES values. Under isothermal conditions, the resulting improvement of sludge disintegration efficacy as compared to atmospheric pressure was by 22-67% and 26-37% for mixed and secondary sludge, respectively. Besides, mean particle diameter (D[4,3]) of the three sludge types decreased respectively from 408, 117, and 110 μm to about 94-97, 37-42, and 36-40 μm regardless of sonication conditions, and the size reduction process was much faster than COD extraction. Copyright © 2013 Elsevier B.V. All rights reserved.

Rheological properties of disintegrated sewage sludge

Science.gov (United States)

Wolski, Paweł

2017-11-01

The rheology of the sludge provides information about the capacity and the flow, which in the case of project tasks for the hydraulic conveying installation is an important control parameter. Accurate knowledge of the rheological properties of sludge requires the designation of rheological models. Models single and multiparameter (Ostwald, Bingham, Herschel-Bulkley'a, and others) allow an approximation of flow curves, and the determination of the boundaries of the flow of modified sludge allows you to control the process compaction or are dewatered sludge undergoing flow. The aim of the study was to determine the rheological parameters and rheological models of sludge conditioned by physical methods before and after the process of anaerobic digestion. So far, studies have shown that the application of conditioning in the preparation of sewage sludge increases shear stress, viscosity as well as the limits of flow in relation to the untreated sludge. Offset yield point by the application of a conditioning agent is associated with decreased flowability tested sludge, which has also been observed by analyzing the structure of the prepared samples. Lowering the yield point, and thus the shear stress was recorded as a result of the fermentation test of disintegrated sludge.

The use of hydrodynamic disintegration as a means to improve anaerobic digestion of activated sludge

OpenAIRE

Machnicka, A; Grűbel, K; Suschka, J

2009-01-01

Disintegration by hydrodynamic cavitation has a positive effect on the degree and rate of sludge anaerobic digestion. By applying hydrodynamic disintegration the lysis of cells occurs in minutes instead of days. The intracellular and extracellular components are set free and are immediately available for biological degradation which leads to an improvement of the subsequent anaerobic process. Hydrodynamic disintegration of the activated sludge results in organic matter and a polymer transfer ...

Dewatering of sludges

International Nuclear Information System (INIS)

Bode, P.

1984-01-01

A filter rig has been designed and built. Simulated magnox and alumino ferric hydroxide sludges have been successfully filtered on this equipment and both types of sludge produced a clear filtrate and a cake. The flow rates were low. The cake often partially remained adhered to the filter membrane instead of dropping clear during the filter cleaning cycle. This filtration technique can only be used on sludges which form a non-binding cake. Permeability of the membrane can be altered by stretching. Irradiation of the membrane showed that it should withstand 20 to 50 M.rads. (author)

Mechanisms and kinetics of granulated sewage sludge combustion.

Science.gov (United States)

Kijo-Kleczkowska, Agnieszka; Środa, Katarzyna; Kosowska-Golachowska, Monika; Musiał, Tomasz; Wolski, Krzysztof

2015-12-01

This paper investigates sewage sludge disposal methods with particular emphasis on combustion as the priority disposal method. Sewage sludge incineration is an attractive option because it minimizes odour, significantly reduces the volume of the starting material and thermally destroys organic and toxic components of the off pads. Additionally, it is possible that ashes could be used. Currently, as many as 11 plants use sewage sludge as fuel in Poland; thus, this technology must be further developed in Poland while considering the benefits of co-combustion with other fuels. This paper presents the results of experimental studies aimed at determining the mechanisms (defining the fuel combustion region by studying the effects of process parameters, including the size of the fuel sample, temperature in the combustion chamber and air velocity, on combustion) and kinetics (measurement of fuel temperature and mass changes) of fuel combustion in an air stream under different thermal conditions and flow rates. The combustion of the sludge samples during air flow between temperatures of 800 and 900°C is a kinetic-diffusion process. This process determines the sample size, temperature of its environment, and air velocity. The adopted process parameters, the time and ignition temperature of the fuel by volatiles, combustion time of the volatiles, time to reach the maximum temperature of the fuel surface, maximum temperature of the fuel surface, char combustion time, and the total process time, had significant impacts. Copyright © 2015 Elsevier Ltd. All rights reserved.

Start-Up Characteristics of a Granule-Based Anammox UASB Reactor Seeded with Anaerobic Granular Sludge

Directory of Open Access Journals (Sweden)

Lei Xiong

2013-01-01

Full Text Available The granulation of anammox sludge plays an important role in the high nitrogen removal performance of the anammox reactor. In this study, anaerobic granular sludge was selected as the seeding sludge to start up anammox reactor in order to directly obtain anammox granules. Results showed that the anammox UASB reactor was successfully started up by inoculating anaerobic granular sludge, with substrate capacity of 4435.2 mg/(L·d and average ammonium and nitrite removal efficiency of 90.36% and 93.29%, respectively. During the start-up course, the granular sludge initially disintegrated and then reaggregated and turned red, suggesting the high anammox performance. Zn-Fe precipitation was observed on the surface of granules during the operation by SEM-EDS, which would impose inhibition to the anammox activity of the granules. Accordingly, it is suggested to relatively reduce the trace metals concentrations, of Fe and Zn in the conventional medium. The findings of this study are expected to be used for a shorter start-up and more stable operation of anammox system.

Start-Up Characteristics of a Granule-Based Anammox UASB Reactor Seeded with Anaerobic Granular Sludge

Science.gov (United States)

Wang, Yun-Yan; Tang, Chong-Jian; Chai, Li-Yuan; Xu, Kang-Que; Song, Yu-Xia

2013-01-01

The granulation of anammox sludge plays an important role in the high nitrogen removal performance of the anammox reactor. In this study, anaerobic granular sludge was selected as the seeding sludge to start up anammox reactor in order to directly obtain anammox granules. Results showed that the anammox UASB reactor was successfully started up by inoculating anaerobic granular sludge, with substrate capacity of 4435.2 mg/(L·d) and average ammonium and nitrite removal efficiency of 90.36% and 93.29%, respectively. During the start-up course, the granular sludge initially disintegrated and then reaggregated and turned red, suggesting the high anammox performance. Zn-Fe precipitation was observed on the surface of granules during the operation by SEM-EDS, which would impose inhibition to the anammox activity of the granules. Accordingly, it is suggested to relatively reduce the trace metals concentrations, of Fe and Zn in the conventional medium. The findings of this study are expected to be used for a shorter start-up and more stable operation of anammox system. PMID:24455691

Investigation of sewage sludge gasification with use of flue gas as a gasifying agent

Directory of Open Access Journals (Sweden)

Maj Izabella

2017-01-01

Full Text Available The paper presents results of investigation of low-temperature sewage sludge gasification with use of flue gas as a gasifying agent. Tests were conducted in a laboratory stand, equipped with a gasification reactor designed and constructed specifically for this purpose. During presented tests, gas mixture with a composition of typical flue gases was used as a gasifying agent. The measuring system ensures online measurements of syngas composition: CO, CO2, H2, CH4. As a result of gasification process a syngas with combustible components has been obtained. The aim of the research was to determine the usability of sewage sludge for indirect cofiring in power boilers with the use of flue gas from the boiler as a gasifying agent and recirculating the syngas to the boiler’s combustion chamber. Results of presented investigation will be used as a knowledge base for industrial-scale sewage sludge gasification process. Furthermore, toxicity of solid products of the process has been determined by the use of Microtox bioassay. Before tests, solid post-gasification residues have been ground to two particle size fractions and extracted into Milli-Q water. The response of test organisms (bioluminescent Aliivibrio fischeri bacteria in reference to a control sample (bacteria exposed to 2% NaCl solution was measured after 5 and 15 minutes of exposure. The obtained toxicity results proved that thermal treatment of sewage sludge by their gasification reduces their toxicity relative to water organisms.

Succession of microbial community and enhanced mechanism of a ZVI-based anaerobic granular sludge process treating chloronitrobenzenes wastewater

Energy Technology Data Exchange (ETDEWEB)

Zhu, Liang, E-mail: felix79cn@hotmail.com [Department of Environmental Engineering, Zhejiang University, Hangzhou 310058 (China); Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety, Hangzhou 310058 (China); Jin, Jie [Department of Environmental Engineering, Zhejiang University, Hangzhou 310058 (China); Lin, Haizhuan [Department of Environmental Engineering, Zhejiang University, Hangzhou 310058 (China); Wenzhou Environmental Protection Design Scientific Institute, Wenzhou 325000 (China); Gao, Kaituo [Department of Environmental Engineering, Zhejiang University, Hangzhou 310058 (China); Xu, Xiangyang, E-mail: xuxy@zju.edu.cn [Department of Environmental Engineering, Zhejiang University, Hangzhou 310058 (China); Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety, Hangzhou 310058 (China)

2015-03-21

Highlights: • The combined ZVI–UASB process was established for the degradation of chloronitrobenzenes. • There were the better shock resistance and buffering capacity for anaerobic acidification in the combined process. • Novel ZVI-based anaerobic granular sludge (ZVI–AGS) was successfully developed. • Adaptive shift of microbial community was significant in ZVI-based anaerobic granular sludge system. - Abstract: The combined zero-valent iron (ZVI) and upflow anaerobic sludge blanket (UASB) process is established for the treatment of chloronitrobenzenes (ClNBs) wastewater, and the succession of microbial community and its enhanced mechanism are investigated in the study. Results showed that compared with the control UASB (R1), the stable COD removal, ClNBs transformation, and dechlorination occurred in the combined system (R2) when operated at influent COD and 3,4-Dichloronitrobenzene (3,4-DClNB) loading rates of 4200–7700 g m{sup −3} d{sup −1} and 6.0–70.0 g m{sup −3} d{sup −1}, and R2 had the better shock resistance and buffering capacity for the anaerobic acidification. The dechlorination for the intermediate products of p-chloroanaline (p-ClAn) to analine (AN) occurred in R2 reactor after 45 days, whereas it did not occur in R1 after a long-term operation. The novel ZVI-based anaerobic granular sludge (ZVI–AGS) was successfully developed in the combined system, and higher microbial activities including ClNB transformation and H{sub 2}/CH{sub 4} production were achieved simultaneously. The dominant bacteria were closely related to the groups of Megasphaera, Chloroflexi, and Clostridium, and the majority of archaea were correlated with the groups of Methanosarcinalesarchaeon, Methanosaetaconcilii, and Methanothrixsoehngenii, which are capable of reductively dechlorinating PCB, HCB, and TCE in anaerobic niche and EPS secretion.

Succession of microbial community and enhanced mechanism of a ZVI-based anaerobic granular sludge process treating chloronitrobenzenes wastewater

International Nuclear Information System (INIS)

Zhu, Liang; Jin, Jie; Lin, Haizhuan; Gao, Kaituo; Xu, Xiangyang

2015-01-01

Highlights: • The combined ZVI–UASB process was established for the degradation of chloronitrobenzenes. • There were the better shock resistance and buffering capacity for anaerobic acidification in the combined process. • Novel ZVI-based anaerobic granular sludge (ZVI–AGS) was successfully developed. • Adaptive shift of microbial community was significant in ZVI-based anaerobic granular sludge system. - Abstract: The combined zero-valent iron (ZVI) and upflow anaerobic sludge blanket (UASB) process is established for the treatment of chloronitrobenzenes (ClNBs) wastewater, and the succession of microbial community and its enhanced mechanism are investigated in the study. Results showed that compared with the control UASB (R1), the stable COD removal, ClNBs transformation, and dechlorination occurred in the combined system (R2) when operated at influent COD and 3,4-Dichloronitrobenzene (3,4-DClNB) loading rates of 4200–7700 g m −3 d −1 and 6.0–70.0 g m −3 d −1 , and R2 had the better shock resistance and buffering capacity for the anaerobic acidification. The dechlorination for the intermediate products of p-chloroanaline (p-ClAn) to analine (AN) occurred in R2 reactor after 45 days, whereas it did not occur in R1 after a long-term operation. The novel ZVI-based anaerobic granular sludge (ZVI–AGS) was successfully developed in the combined system, and higher microbial activities including ClNB transformation and H 2 /CH 4 production were achieved simultaneously. The dominant bacteria were closely related to the groups of Megasphaera, Chloroflexi, and Clostridium, and the majority of archaea were correlated with the groups of Methanosarcinalesarchaeon, Methanosaetaconcilii, and Methanothrixsoehngenii, which are capable of reductively dechlorinating PCB, HCB, and TCE in anaerobic niche and EPS secretion

[Effect of different sludge retention time (SRT) on municipal sewage sludge bioleaching continuous plug flow reaction system].

Science.gov (United States)

Liu, Fen-Wu; Zhou, Li-Xiang; Zhou, Jun; Jiang, Feng; Wang, Dian-Zhan

2012-01-01

A plug-flow bio-reactor of 700 L working volume for sludge bioleaching was used in this study. The reactor was divided into six sections along the direction of the sludge movement. Fourteen days of continuous operation of sludge bioleaching with different sludge retention time (SRT) under the condition of 1.2 m3 x h(-1) aeration amount and 4 g x L(-1) of microbial nutritional substance was conducted. During sludge bioleaching, the dynamic changes of pH, DO, dewaterability (specific resistance to filtration, SRF) of sewage sludge in different sections were investigated in the present study. The results showed that sludge pH were maintained at 5.00, 3.00, 2.90, 2.70, 2.60 and 2.40 from section 1 to section 6 and the SRF of sludge was drastically decreased from initial 0.64 x 10(13) m x kg(-1) to the final 0.33 x 10(13) m x kg(-1) when bioleaching system reached stable at hour 72 with SRT 2.5d. In addition, the sludge pH were maintained at 5.10, 4.10, 3.20, 2.90, 2.70 and 2.60, the DO value were 0.43, 1.47, 3.29, 4.76, 5.75 and 5.88 mg x L(-1) from section 1 to section 6, and the SRF of sludge was drastically decreased from initial 0.56 x 10(13) to the final 0.20 x 10(13) m x kg(-1) when bioleaching system reached stable at hour 120 with SRT 2 d. The pH value was increased to 3.00 at section 6 at hour 48 h with SRT 1.25 d. The bioleaching system imbalanced in this operation conditions because of the utilization efficiency of microbial nutritional substance by Acidibacillus spp. was decreased. The longer sludge retention time, the easier bioleaching system reached stable. 2 d could be used as the optimum sludge retention time in engineering application. The bioleached sludge was collected and dewatered by plate-and-frame filter press to the moisture content of dewatered sludge cake under 60%. This study would provide the necessary data to the engineering application on municipal sewage sludge bioleaching.

Analytical methodologies based on LC-MS/MS for monitoring selected emerging compounds in liquid and solid phases of the sewage sludge.

Science.gov (United States)

Boix, C; Ibáñez, M; Fabregat-Safont, D; Morales, E; Pastor, L; Sancho, J V; Sánchez-Ramírez, J E; Hernández, F

2016-01-01

In this work, two analytical methodologies based on liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) were developed for quantification of emerging pollutants identified in sewage sludge after a previous wide-scope screening. The target list included 13 emerging contaminants (EC): thiabendazole, acesulfame, fenofibric acid, valsartan, irbesartan, salicylic acid, diclofenac, carbamazepine, 4-aminoantipyrine (4-AA), 4-acetyl aminoantipyrine (4-AAA), 4-formyl aminoantipyrine (4-FAA), venlafaxine and benzoylecgonine. The aqueous and solid phases of the sewage sludge were analyzed making use of Solid-Phase Extraction (SPE) and UltraSonic Extraction (USE) for sample treatment, respectively. The methods were validated at three concentration levels: 0.2, 2 and 20 μg L(-1) for the aqueous phase, and 50, 500 and 2000 μg kg(-1) for the solid phase of the sludge. In general, the method was satisfactorily validated, showing good recoveries (70-120%) and precision (RSD metabolites of dipyrone had not been studied before in sewage sludge.

Sludge pumping in water treatment

International Nuclear Information System (INIS)

Solar Manuel, M. A.

2010-01-01

In water treatment processes is frequent to separate residual solids, with sludge shape, and minimize its volume in a later management. the technologies to applicate include pumping across pipelines, even to long distance. In wastewater treatment plants (WWTP), the management of these sludges is very important because their characteristics affect load losses calculation. Pumping sludge can modify its behavior and pumping frequency can concern treatment process. This paper explains advantages and disadvantages of different pumps to realize transportation sludge operations. (Author) 11 refs.

Hydrothermal Liquefaction and Upgrading of Municipal Wastewater Treatment Plant Sludge: A Preliminary Techno-Economic Analysis

Energy Technology Data Exchange (ETDEWEB)

Snowden-Swan, Lesley J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zhu, Yunhua [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jones, Susanne B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Elliott, Douglas C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Schmidt, Andrew J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hallen, Richard T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Billing, Justin M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hart, Todd R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fox, Samuel P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Maupin, Gary D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2016-06-08

A preliminary process model and techno-economic analysis (TEA) was completed for fuel produced from hydrothermal liquefaction (HTL) of sludge waste from a municipal wastewater treatment plant (WWTP) and subsequent biocrude upgrading. The model is adapted from previous work by Jones et al. (2014) for algae HTL, using experimental data generated in fiscal year 2015 (FY15) bench-scale HTL testing of sludge waste streams. Testing was performed on sludge samples received from MetroVancouver’s Annacis Island WWTP (Vancouver, B.C.) as part of a collaborative project with the Water Environment and Reuse Foundation (WERF). The full set of sludge HTL testing data from this effort will be documented in a separate report to be issued by WERF. This analysis is based on limited testing data and therefore should be considered preliminary. Future refinements are necessary to improve the robustness of the model, including a cross-check of modeled biocrude components with the experimental GCMS data and investigation of equipment costs most appropriate at the smaller scales used here. Environmental sustainability metrics analysis is also needed to understand the broader impact of this technology pathway. The base case scenario for the analysis consists of 10 HTL plants, each processing 100 dry U.S. ton/day (92.4 ton/day on a dry, ash-free basis) of sludge waste and producing 234 barrel per stream day (BPSD) biocrude, feeding into a centralized biocrude upgrading facility that produces 2,020 barrel per standard day of final fuel. This scale was chosen based upon initial wastewater treatment plant data collected by the resource assessment team from the EPA’s Clean Watersheds Needs Survey database (EPA 2015a) and a rough estimate of what the potential sludge availability might be within a 100-mile radius. In addition, we received valuable feedback from the wastewater treatment industry as part of the WERF collaboration that helped form the basis for the selected HTL and upgrading

Component-based development process and component lifecycle

NARCIS (Netherlands)

Crnkovic, I.; Chaudron, M.R.V.; Larsson, S.

2006-01-01

The process of component- and component-based system development differs in many significant ways from the "classical" development process of software systems. The main difference is in the separation of the development process of components from the development process of systems. This fact has a

RELATIONSHIP BETWEEN SLUDGE DEWATERABILITY NUMBER ...

African Journals Online (AJOL)

A representative of a sludge sample collected from the same source was filtered under the same environmental condition and the result analysed with two different concepts. One method of analysis uses Sludge Dewaterability Number, while the second employed the Carman's Specific resistance concept in sludge ...

Modeling of Evaporation Losses in Sewage Sludge Drying Bed ...

African Journals Online (AJOL)

A model for evaporation losses in sewage sludge drying bed was derived from first principles. This model was developed based on the reasoning that the rate at which evaporation is taking place is directly proportional to the instantaneous quantity of water in the sludge. The aim of this work was to develop a model to assist ...

Impact of sludge stabilization processes and sludge origin (urban or hospital) on the mobility of pharmaceutical compounds following sludge landspreading in laboratory soil-column experiments.

Science.gov (United States)

Lachassagne, Delphine; Soubrand, Marilyne; Casellas, Magali; Gonzalez-Ospina, Adriana; Dagot, Christophe

2015-11-01

This study aimed to determine the effect of sludge stabilization treatments (liming and anaerobic digestion) on the mobility of different pharmaceutical compounds in soil amended by landspreading of treated sludge from different sources (urban and hospital). The sorption and desorption potential of the following pharmaceutical compounds: carbamazepine (CBZ), ciprofloxacin (CIP), sulfamethoxazole (SMX), salicylic acid (SAL), ibuprofen (IBU), paracetamol (PAR), diclofenac (DIC), ketoprofen (KTP), econazole (ECZ), atenolol (ATN), and their solid-liquid distribution during sludge treatment (from thickening to stabilization) were investigated in the course of batch testing. The different sludge samples were then landspread at laboratory scale and leached with an artificial rain simulating 1 year of precipitation adapted to the surface area of the soil column used. The quality of the resulting leachate was investigated. Results showed that ibuprofen had the highest desorption potential for limed and digested urban and hospital sludge. Ibuprofen, salicylic acid, diclofenac, and paracetamol were the only compounds found in amended soil leachates. Moreover, the leaching potential of these compounds and therefore the risk of groundwater contamination depend mainly on the origin of the sludge because ibuprofen and diclofenac were present in the leachates of soils amended with urban sludge, whereas paracetamol and salicylic acid were found only in the leachates of soils amended with hospital sludge. Although carbamazepine, ciprofloxacin, sulfamethoxazole, ketoprofen, econazole, and atenolol were detected in some sludge, they were not present in any leachate. This reflects either an accumulation and/or (bio)degradation of these compounds (CBZ, CIP, SMX, KTP, ECZ, and ATN ), thus resulting in very low mobility in soil. Ecotoxicological risk assessment, evaluated by calculating the risk quotients for each studied pharmaceutical compound, revealed no high risk due to the

Color pollution control in textile dyeing industry effluents using tannery sludge

Directory of Open Access Journals (Sweden)

Sajjala Sreedhar Reddy

2008-12-01

Full Text Available Effective treatment of dyestuff containing textile dyeing industry effluents require advanced treatment technologies such as adsorption for the removal of dyestuffs. Powdered commercial coal based activated carbon has been the most widely used adsorbent for the removal of dyestuffs from dyeing industry effluents. As an alternative to commercial coal based activated carbon, activated carbon prepared from dried tannery sludge was used as an adsorbent for dyestuff removal from simulated textile dying industry effluent in this study. The color removal performance of tannery sludge derived activated carbon and commercial coal based activated carbon has been investigated using parameters such as adsorbent dosage, initial dye concentration, pH and temperature. It was found that tannery sludge derived activated carbon exhibits dye removal efficiency that is about 80–90 % of that observed with commercial coal based activated carbon. The amount of dye adsorbed on to tannery sludge derived activated carbon is lower compared with commercial activated carbon at equilibrium and dye adsorption capacity increased with increase of initial dye concentration and temperature, and deceasing pH. It was found that the Langmuir isotherm appears to fit the isotherm data better than the Freundlich isotherm. The leachate of heavy metals from tannery sludge derived activated carbon to the environment is very low, which are within the standard limit of industrial effluent and leachable substances.

Sludge Settling Rate Observations and Projections at the Savannah River Site - 13238

Energy Technology Data Exchange (ETDEWEB)

Gillam, Jeffrey M.; Shah, Hasmukh B.; Keefer, Mark T. [Savannah River Remediation LLC, Aiken SC 29808 (United States)

2013-07-01

Since 2004, sludge batches have included a high percentage of stored sludge generated from the H- modified (HM) process. The slow-settling nature of HM sludge means that the settling is often the major part of the washing tank quiescent period between required pump runs to maintain flammability control. Reasonable settling projections are needed to wash soluble salts from sludge in an efficient manner, to determine how much sludge can be washed in a batch within flammability limits, and to provide composition projections for batch qualification work done in parallel with field preparation. Challenges to providing reasonably accurate settling projections include (1) large variations in settling behavior from tank-to-tank, (2) accounting for changing initial concentrations, sludge masses, and combinations of different sludge types, (3) changing the settling behavior upon dissolving some sludge compounds, and (4) sludge preparation schedules that do not allow for much data collection for a particular sludge before washing begins. Scaling from laboratory settling tests has provided inconsistent results. Several techniques have been employed to improve settling projections and therefore the overall batch preparation efficiency. Before any observations can be made on a particular sludge mixture, projections can only be made based on historical experience with similar sludge types. However, scaling techniques can be applied to historical settling models to account for different sludge masses, concentrations, and even combinations of types of sludge. After sludge washing/settling cycles begin, the direct measurement of the sludge height, once generally limited to a single turbidity meter measurement per settle period, is now augmented by examining the temperature profile in the settling tank, to help determine the settled sludge height over time. Recently, a settling model examined at PNNL [1,2,3] has been applied to observed thermocouple and turbidity meter readings to

Modelling Analysis of Sewage Sludge Amended Soil

DEFF Research Database (Denmark)

Sørensen, P. B.; Carlsen, L.; Vikelsøe, J.

the plant effluent. The focus in this work is the top soil as this layer is important for the fate of a xenobiotic substance due to the high biological activity. A simple model for the top soil is used where the substance is assumed homogeneously distributed as suggested in the European Union System......The topic is risk assessment of sludge supply to agricultural soil in relation to xenobiotics. A large variety of xenobiotics arrive to the wastewater treatment plant in the wastewater. Many of these components are hydrophobic and thus will accumulate in the sludge solids and are removed from...... for the Evaluation of Substances (EUSES). It is shown how the fraction of substance mass, which is leached, from the top soil is a simple function of the ratio between the degradation half lifetime and the adsorption coefficient. This model can be used in probabilistic risk assessment of agricultural soils...

Influence of organic matter transformations on the bioavailability of heavy metals in a sludge base compost

International Nuclear Information System (INIS)

Molina, M. J.; Ingelmo, F.; Soriano, M. D.; Gallardo, A.; Lapena, L.

2009-01-01

The agricultural use of anaerobically digested sewage sludge (ADSS) as stable, mature compost implies knowing its total content in heavy metals and their bioavailability. since the chemical form of the metal in the sewage sludge-based compost depends on the effect of stabilization and maturation of the organic material during composting, the objective of this work was to examine the relationships between the changes in the organic matter content and humus fractions, and the bioavailability of heavy metals in a mixture of ADSS and wood chips (70:30 on wet basis) with an initial C/N ratio of 30.4, during its aerobic batch composting at 30 degree centigrade of external temperature in an open type lab-scale reactor with-out lixiviation. (Author)

Influence of organic matter transformations on the bioavailability of heavy metals in a sludge base compost

Energy Technology Data Exchange (ETDEWEB)

Molina, M. J.; Ingelmo, F.; Soriano, M. D.; Gallardo, A.; Lapena, L.

2009-07-01

The agricultural use of anaerobically digested sewage sludge (ADSS) as stable, mature compost implies knowing its total content in heavy metals and their bioavailability. since the chemical form of the metal in the sewage sludge-based compost depends on the effect of stabilization and maturation of the organic material during composting, the objective of this work was to examine the relationships between the changes in the organic matter content and humus fractions, and the bioavailability of heavy metals in a mixture of ADSS and wood chips (70:30 on wet basis) with an initial C/N ratio of 30.4, during its aerobic batch composting at 30 degree centigrade of external temperature in an open type lab-scale reactor with-out lixiviation. (Author)

Settling properties of aerobic granular sludge (AGS) and aerobic granular sludge molasses (AGSM)

Science.gov (United States)

Mat Saad, Azlina; Aini Dahalan, Farrah; Ibrahim, Naimah; Yasina Yusuf, Sara; Aqlima Ahmad, Siti; Khalil, Khalilah Abdul

2018-03-01

Aerobic granulation technology is applied to treat domestic and industrial wastewater. The Aerobic granular sludge (AGS) cultivated has strong properties that appears to be denser and compact in physiological structure compared to the conventional activated sludge. It offers rapid settling for solid:liquid separation in wastewater treatment. Aerobic granules were developed using sequencing batch reactor (SBR) with intermittent aerobic - anaerobic mode with 8 cycles in 24 hr. This study examined the settling velocity performance of cultivated aerobic granular sludge (AGS) and aerobic granular sludge molasses (AGSM). The elemental composition in both AGS and AGSM were determined using X-ray fluorescence (XRF). The results showed that AGSM has higher settling velocity 30.5 m/h compared to AGS.

Electroosmotic dewatering of chalk sludge, iron hydroxide sludge, wet fly ash and biomass

Energy Technology Data Exchange (ETDEWEB)

Hansen, H.K.; Kristensen, I.V.; Ottosen, L.M.; Villumsen, A. [Dept. of Geology and Geotechnical Engineering, The Technical Univ. of Denmark, Lyngby (Denmark)

2001-07-01

Electroosmotic dewatering has been tested in laboratory cells for 4 different porous materials: chalk sludge, iron hydroxide sludge, wet fly ash and biomass sludge from enzyme production. In all cases it was possible to remove water when passing electric DC current through the material. Casagrande's coefficients for the three materials where determined at different water contents. In the electroosmotic experiments shown in this work chalk can be dewatered from 40% to 79% DM (dry matter), fly ash from 75 to 82% DM, iron hydroxide sludge from 2.7 to 19% DM and biomass from 3 to 33% DM. The process was not optimised indicating that higher dry matter contents could be achieved. (orig.)

Enhancing faecal sludge management in peri-urban areas of Lusaka through faecal sludge valorisation: challenges and opportunities

Science.gov (United States)

Tembo, J. M.; Nyirenda, E.; Nyambe, I.

2017-03-01

Lusaka, the capital city of Zambia, has two million inhabitants with 70% residing in peri-urban areas. Ninety (90) % of this population employ pit latrines for excretion generating approximately 22,680 tons of faecal sludge per annum. This sludge is inadequately managed hence of the generated amount, over 60% remains within the residential environment thereby compromising both the environment and public health. To foster a solution to this problem, a study was commissioned to assess faecal sludge valorisation potential and how it would impact on Faecal Sludge Management. The study evaluated policy, institutional and regulatory frameworks, sanitation practices including latrine construction and usage aspects and also characterised the faecal sludge for selected parameters relevant to valorisation. Four peri-urban areas were adopted as study sites. Policy issues together with existing institutional and regulatory frameworks were assessed through literature review. Sanitation practices were evaluated through physical observations, focus group discussions, interviews and questionnaire administration. Faecal sludge characterisation was through sampling and analysis. It was observed that there are policy gaps in fostering faecal sludge valorisation. Sanitation practices and latrines construction also do not favour valorisation. The quality of the raw sludge has potential for valorisation though again, some parameters like solid waste content require drastic changes in sanitation practices in order not to compromise the reuse potential of the sludge. It was concluded that if faecal sludge management is to be enhanced through valorisation, there is need to have policies promoting pit latrine faecal sludge reuse and strengthened regulatory and institutional frameworks in this respect.

Novel dark fermentation involving bioaugmentation with constructed bacterial consortium for enhanced biohydrogen production from pretreated sewage sludge

Energy Technology Data Exchange (ETDEWEB)

Kotay, Shireen Meher; Das, Debabrata [Department of Biotechnology, Indian Institute of Technology, Kharagpur (India)

2009-09-15

The present study summarizes the observations on various nutrient and seed formulation methods using sewage sludge that have been aimed at ameliorating the biohydrogen production potential. Pretreatment methods viz., acid/base treatment, heat treatment, sterilization, freezing-thawing, microwave, ultrasonication and chemical supplementation were attempted on sludge. It was observed that pretreatment was essential not only to reduce the needless, competitive microbial load but also to improve the nutrient solublization of sludge. Heat treatment at 121 C for 20 min was found to be most effective in reducing the microbial load by 98% and hydrolyzing the organic fraction of sludge. However, this pretreatment alone was either not sufficient or inconsistent in developing a suitable microbial consortium for hydrogen production. Hydrogen yield was found to improve 1.5-4 times upon inoculation with H{sub 2}-producing microorganisms. A defined microbial consortium was developed consisting of three established bacteria viz., Enterobacter cloacae IIT-BT 08, Citrobacter freundii IIT-BT L139 and Bacillus coagulans IIT-BT S1. Following pretreatments soluble proteins and lipids (the major component of the sludge) were also found to be consumed besides carbohydrates. This laid out the concurrent proteolytic/lipolytic ability of the developed H{sub 2}-producing consortium. 1:1:1 v/v ratio of these bacteria in consortium was found to give the maximum yield of H{sub 2} from sludge, 39.15 ml H{sub 2}/g COD{sub reduced}. 15%v/v dilution and supplementation with 0.5%w/v cane molasses prior to heat treatment was found to further improve the yield to 41.23 ml H{sub 2}/g COD{sub reduced}. (author)

An experimental study of low concentration sludge settling velocity under turbulent condition.

Science.gov (United States)

Guo, Lisha; Zhang, Daijun; Xu, Danyu; Chen, Yuan

2009-05-01

Particle Image Velocimetry (PIV) was used to study the settling of activated sludge flocs under turbulent flow conditions. Experimental results showed that a larger particle diameter led to a higher settling velocity while the higher turbulence intensity led to lower settling velocity. Based on the measurements a mathematical relation has been derived which correlates the settling velocity for individual sludge flocs under turbulent conditions through a modified Vesilind equation. Settling velocity shows a power-type relation to sludge particle diameter and an exponential-type relation with turbulence intensity and sludge concentration.

Properties of bacterial radioresistance observed in sewage sludge

Energy Technology Data Exchange (ETDEWEB)

Watanabe, H; Ito, H; Takehisa, M [Japan Atomic Energy Research Inst., Takasaki, Gunma. Takasaki Radiation Chemistry Research Establishment; Iizuka, H

1981-09-01

The changes in radiosensitivities of bacteria in sludge were investigated. The coliforms are more radioresistant in raw sludge than in cake (dewatered sludge). This radioresistance of coliforms was observed not only in raw sludge but also in the cake diluted with water. The radioresistance was independent of the difference of treatment plant, kind of sludge, and season. The oxygen effect on the radioresistance was not observed, but the resistance was changed during storage of sludge. Escherichia coli isolated from sludge was radiosensitive in buffer, but its radiosensitivity was protected by the water-extracts of sludge. On the other hand, radioresistant bacteria were present in total bacteria of sludge irradiated at 2 Mrad. However, the dominant flora in the irradiated sludge consisted of radiosensitive bacteria (mainly Pseudomonas). When a strain of radiosensitive Pseudomonas was irradiated in raw sludge and diluted cake, the radiosensitivity was remarkably protected. From these results, it is suggested that a factor affecting the radiosensitivity of bacteria is present in sludge.

Properties of bacterial radioresistance observed in sewage sludge

International Nuclear Information System (INIS)

Watanabe, Hiroshi; Ito, Hitoshi; Takehisa, Masaaki; Iizuka, Hiroshi.

1981-01-01

The changes in radiosensitivities of bacteria in sludge were investigated. The coliforms are more radioresistant in raw sludge than in cake (dewatered sludge). This radioresistance of coliforms was observed not only in raw sludge but also in the cake diluted with water. The radioresistance was independent of the difference of treatment plant, kind of sludge, and season. The oxygen effect on the radioresistance was not observed, but the resistance was changed during storage of sludge. Escherichia coli isolated from sludge was radiosensitive in buffer, but its radiosensitivity was protected by the water-extracts of sludge. On the other hand, radioresistant bacteria were present in total bacteria of sludge irradiated at 2 Mrad. However, the dominant flora in the irradiated sludge consisted of radiosensitive bacteria (mainly Pseudomonas). When a strain of radiosensitive Pseudomonas was irradiated in raw sludge and diluted cake, the radiosensitivity was remarkably protected. From these results, it is suggested that a factor affecting the radiosensitivity of bacteria is present in sludge. (author)

Treatment of off-gas from lagoon sludge thermal decomposition

International Nuclear Information System (INIS)

Hwang, D. S.; Oh, J. H.; Choi, Y. D.; Hwang, S. T.; Park, J. H.; Ga, M. J.

2005-01-01

Korea Atomic Energy Research Institute (KAERI) has launched a decommissioning program of the uranium conversion plant in 2001. The treatment of the sludge waste, which was generated during the operation of the plant and stored in the lagoon, is one of the most important tasks in the decommissioning program of the plant. The major compounds of the lagoon sludge are ammonium nitrate, sodium nitrate, calcium nitrate, calcium carbonate, and uranium compounds. The minor compounds are iron, magnesium, aluminum, silicon and phosphorus. A treatment process of the sludge was developed as figure 1 based on the results of the sludge characteristics and the developed treatment technologies. A treatment of off-gas evolved from the nitrate salts thermal decomposition is one of the important process. Off-gas treatment by using a selective catalytic reduction (SCR) method was investigated in this study

Combustion characteristics of biodried sewage sludge.

Science.gov (United States)

Hao, Zongdi; Yang, Benqin; Jahng, Deokjin

2018-02-01

In this study, effects of biodrying on the characteristics of sewage sludge and the subsequent combustion behavior were investigated. 7-Day of biodrying removed 49.78% of water and 23.17% of VS initially contained in the sewage sludge and increased lower heating value (LHV) by 37.87%. Meanwhile, mass contents of C and N decreased from 36.25% and 6.12% to 32.06% and 4.82%, respectively. Surface of the biodried sewage sludge (BDSS) appeared granulated and multi-porous, which was thought to facilitate air transfer during combustion. According to thermogravimetric (TG) analysis coupled with mass spectrometer (MS) with a heating rate of 10 °C/min from 35 °C to 1000 °C, thermally-dried sewage sludge (TDSS) and BDSS lost 74.39% and 67.04% of the initial mass, respectively. In addition, combustibility index (S) of BDSS (8.67 × 10 -8  min -2  K -3 ) was higher than TDSS. TG-MS analyses also showed that less nitrogenous gases were generated from BDSS than TDSS. It was again showed that the average CO and NO concentrations in exit gas from isothermal combustion of BDSS were lower than those from TDSS, especially at low temperatures (≤800 °C). Based on these results, it was concluded that biodrying of sewage sludge was an energy-efficient water-removal method with less emission of air pollutants when BDSS was combusted. Copyright © 2017 Elsevier Ltd. All rights reserved.

Strength Measurements of Archive K Basin Sludge Using a Soil Penetrometer

International Nuclear Information System (INIS)

Delegard, Calvin H.; Schmidt, Andrew J.; Chenault, Jeffrey W.

2011-01-01

Spent fuel radioactive sludge present in the K East and K West spent nuclear fuel storage basins now resides in the KW Basin in six large underwater engineered containers. The sludge will be dispositioned in two phases under the Sludge Treatment Project: (1) hydraulic retrieval into sludge transport and storage containers (STSCs) and transport to interim storage in Central Plateau and (2) retrieval from the STSCs, treatment, and packaging for shipment to the Waste Isolation Pilot Plant. In the years the STSCs are stored, sludge strength is expected to increase through chemical reaction, intergrowth of sludge crystals, and compaction and dewatering by settling. Increased sludge strength can impact the type and operation of the retrieval equipment needed prior to final sludge treatment and packaging. It is important to determine whether water jetting, planned for sludge retrieval from STSCs, will be effective. Shear strength is a property known to correlate with the effectiveness of water jetting. Accordingly, the unconfined compressive strengths (UCS) of archive K Basin sludge samples and sludge blends were measured using a pocket penetrometer modified for hot cell use. Based on known correlations, UCS values can be converted to shear strengths. Twenty-six sludge samples, stored in hot cells for a number of years since last being disturbed, were identified as potential candidates for UCS measurement and valid UCS measurements were made for twelve, each of which was found as moist or water-immersed solids at least 1/2-inch deep. Ten of the twelve samples were relatively weak, having consistencies described as 'very soft' to 'soft'. Two of the twelve samples, KE Pit and KC-4 P250, were strong with 'very stiff' and 'stiff' consistencies described, respectively, as 'can be indented by a thumb nail' or 'can be indented by thumb'. Both of these sludge samples are composites collected from KE Basin floor and Weasel Pit locations. Despite both strong sludges having

Strength Measurements of Archive K Basin Sludge Using a Soil Penetrometer

Energy Technology Data Exchange (ETDEWEB)

Delegard, Calvin H.; Schmidt, Andrew J.; Chenault, Jeffrey W.

2011-12-06

Spent fuel radioactive sludge present in the K East and K West spent nuclear fuel storage basins now resides in the KW Basin in six large underwater engineered containers. The sludge will be dispositioned in two phases under the Sludge Treatment Project: (1) hydraulic retrieval into sludge transport and storage containers (STSCs) and transport to interim storage in Central Plateau and (2) retrieval from the STSCs, treatment, and packaging for shipment to the Waste Isolation Pilot Plant. In the years the STSCs are stored, sludge strength is expected to increase through chemical reaction, intergrowth of sludge crystals, and compaction and dewatering by settling. Increased sludge strength can impact the type and operation of the retrieval equipment needed prior to final sludge treatment and packaging. It is important to determine whether water jetting, planned for sludge retrieval from STSCs, will be effective. Shear strength is a property known to correlate with the effectiveness of water jetting. Accordingly, the unconfined compressive strengths (UCS) of archive K Basin sludge samples and sludge blends were measured using a pocket penetrometer modified for hot cell use. Based on known correlations, UCS values can be converted to shear strengths. Twenty-six sludge samples, stored in hot cells for a number of years since last being disturbed, were identified as potential candidates for UCS measurement and valid UCS measurements were made for twelve, each of which was found as moist or water-immersed solids at least 1/2-inch deep. Ten of the twelve samples were relatively weak, having consistencies described as 'very soft' to 'soft'. Two of the twelve samples, KE Pit and KC-4 P250, were strong with 'very stiff' and 'stiff' consistencies described, respectively, as 'can be indented by a thumb nail' or 'can be indented by thumb'. Both of these sludge samples are composites collected from KE Basin floor and

Vitrification Studies with DOE Low-Level Mixed Waste Wastewater Treatment Sludges

International Nuclear Information System (INIS)

Cicero, C.A.; Andrews, M.K.; Bickford, D.F.; Hewlett, K.J.; Bennert, D.M.; Overcamp, T.J.

1995-01-01

Vitrification studies with simulated Low Level Mixed Waste (LLMW) sludges were performed at the Savannah River Technology Center (SRTC). These studies focused on finding the optimum glass compositions for four simulated LLMW wastewater treatment sludges and were based on both crucible-scale and pilot-scale studies. Optimum compositions were determined based on the maximum waste loading achievable without sacrificing glass integrity

SLUDGE WASHING AND DEMONSTRATION OF THE DWPF FLOWSHEET IN THE SRNL SHIELDED CELLS FOR SLUDGE BATCH 6 QUALIFICATION

Energy Technology Data Exchange (ETDEWEB)

Pareizs, J.; Pickenheim, B.; Bannochie, C.; Billings, A.; Bibler, N.; Click, D.

2010-10-01

Prior to initiating a new sludge batch in the Defense Waste Processing Facility (DWPF), Savannah River National Laboratory (SRNL) is required to simulate this processing, including Chemical Process Cell (CPC) simulation, waste glass fabrication, and chemical durability testing. This report documents this simulation for the next sludge batch, Sludge Batch 6 (SB6). SB6 consists of Tank 12 material that has been transferred to Tank 51 and subjected to Low Temperature Aluminum Dissolution (LTAD), Tank 4 sludge, and H-Canyon Pu solutions. Following LTAD and the Tank 4 addition, Liquid Waste Operations (LWO) provided SRNL a 3 L sample of Tank 51 sludge for SB6 qualification. Pu solution from H Canyon was also received. SB6 qualification included washing the sample per LWO plans/projections (including the addition of Pu from H Canyon), DWPF CPC simulations, waste glass fabrication (vitrification), and waste glass characterization and chemical durability evaluation. The following are significant observations from this demonstration. Sludge settling improved slightly as the sludge was washed. SRNL recommended (and the Tank Farm implemented) one less wash based on evaluations of Tank 40 heel projections and projections of the glass composition following transfer of Tank 51 to Tank 40. Thorium was detected in significant quantities (>0.1 wt % of total solids) in the sludge. In past sludge batches, thorium has been determined by Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS), seen in small quantities, and reported with the radionuclides. As a result of the high thorium, SRNL-AD has added thorium to their suite of Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) elements. The acid stoichiometry for the DWPF Sludge Receipt and Adjustment Tank (SRAT) processing of 115%, or 1.3 mol acid per liter of SRAT receipt slurry, was adequate to accomplish some of the goals of SRAT processing: nitrite was destroyed to below 1,000 mg/kg and mercury was removed to

Bacterial regrowth potential in alkaline sludges from open-sun and covered sludge drying beds

Energy Technology Data Exchange (ETDEWEB)

Alkan, U.; Topac, F.O.; Birden, B.; Baskaya, H.S. [Uludag University, Gorukle (Turkey). Dept. of Environmnetal Engineering

2007-10-15

The aim of this study was to compare the regrowth potentials of wastewater sludges dried in two pilot-scale drying processes namely, Open-Sun Sludge Drying Bed (OSDB) and Covered Sludge Drying Bed (CSDB). Quicklime and/or coal fly ash were added to raw sludge samples prior to drying processes in order to enhance bacterial inactivation. Following three drying cycles (March-April, June-July and August-October), sludge samples were taken from the beds for the regrowth experiments. Addition of alkaline materials prevented the regrowth of faecal coliforms in all rewetted samples except for the samples obtained after the rainfall events in OSDB. Rewetting of these samples in the regrowth experiments increased faecal coliform numbers by 3.5-7 log units. In contradiction, the observed bacterial numbers in rewetted alkaline samples from CSDB were below the EPA Class B criterion (2 million MPN g{center_dot} 1) dry sludge). The combination of additional heat from solar collectors, protection from the rain and the unfavourable living conditions owing to alkaline materials appeared to inactivate bacteria more effectively in CSDB and hence eliminated regrowth potential more efficiently.

Occurrence of high-tonnage anionic surfactants into Spanish sewage sludge

Energy Technology Data Exchange (ETDEWEB)

Cantarero, S.; Prieto, C. A.; Lopez, I.; Berna, J. L.

2009-07-01

The sewage Sludge directive 86/278/EEc seeks to encourage the disposal of sewage sludge in agriculture applications and regulate its use to prevent harmful effects on the soil environment. currently, the sewage sludge Directive is under revision and a possible cut-off limit for some organic chemicals (including linear alkylbenzene sulphonates. LAS, the main synthetic anionic surfactant) is to be implemented. This legal limit is based on monitoring studies carried out in Scandinavian countries, being strongly rejected by most EU countries since the Nordic situations was regarded as not representative. (Author)

Occurrence of high-tonnage anionic surfactants into Spanish sewage sludge

International Nuclear Information System (INIS)

Cantarero, S.; Prieto, C. A.; Lopez, I.; Berna, J. L.

2009-01-01

The sewage Sludge directive 86/278/EEc seeks to encourage the disposal of sewage sludge in agriculture applications and regulate its use to prevent harmful effects on the soil environment. currently, the sewage sludge Directive is under revision and a possible cut-off limit for some organic chemicals (including linear alkylbenzene sulphonates. LAS, the main synthetic anionic surfactant) is to be implemented. This legal limit is based on monitoring studies carried out in Scandinavian countries, being strongly rejected by most EU countries since the Nordic situations was regarded as not representative. (Author)

Sludge Washing and Demonstration of the DWPF Nitric/Formic Flowsheet in the SRNL Shielded Cells for Sludge Batch 9 Qualification

Energy Technology Data Exchange (ETDEWEB)

Pareizs, J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Newell, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Martino, C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Crawford, C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Johnson, F. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2016-11-01

Savannah River National Laboratory (SRNL) was requested by Savannah River Remediation (SRR) to qualify the next batch of sludge – Sludge Batch 9 (SB9). Current practice is to prepare sludge batches in Tank 51 by transferring sludge to Tank 51 from other tanks. The sludge is washed and transferred to Tank 40, the current Defense Waste Process Facility (DWPF) feed tank. Prior to sludge transfer from Tank 51 to Tank 40, the Tank 51 sludge must be qualified. SRNL qualifies the sludge in multiple steps. First, a Tank 51 sample is received, then characterized, washed, and again characterized. SRNL then demonstrates the DWPF Chemical Process Cell (CPC) flowsheet with the sludge. The final step of qualification involves chemical durability measurements of glass fabricated in the DWPF CPC demonstrations. In past sludge batches, SRNL had completed the DWPF demonstration with Tank 51 sludge. For SB9, SRNL has been requested to process a blend of Tank 51 and Tank 40 at a targeted ratio of 44% Tank 51 and 56% Tank 40 on an insoluble solids basis.

From municipal/industrial wastewater sludge and FOG to fertilizer: A proposal for economic sustainable sludge management.

Science.gov (United States)

Bratina, Božidar; Šorgo, Andrej; Kramberger, Janez; Ajdnik, Urban; Zemljič, Lidija Fras; Ekart, Janez; Šafarič, Riko

2016-12-01

After a ban on the depositing of untreated sludge in landfills, the sludge from municipal and industrial water-treatment plants can be regarded as a problem. Waste products of the water treatment process can be a problem or an opportunity - a source for obtaining raw materials. In the European Union, raw sludge and fats, oil and grease (FOG) from municipal and industrial wastewater treatment plants (WWTP) cannot be deposited in any natural or controlled environment. For this reason, it must be processed (stabilized, dried) to be used later as a fertilizer, building material, or alternative fuel source suitable for co-incineration in high temperature furnaces (power plants or concrete plants). The processes of drying sludge, where heat and electricity are used, are energy consuming and economically unattractive. Beside energy efficiency, the main problem of sludge drying is in its variability of quality as a raw material. In addition to this, sludge can be contaminated by a number of organic and inorganic pollutants and organisms. Due to the presence or absence of pollutants, different end products can be economically interesting. For example, if the dried sludge contains coliform bacteria, viruses, helminths eggs or smaller quantities of heavy metals, it cannot be used as a fertilizer but can still be used as a fuel. The objectives of the current article is to present a batch-processing pilot device of sludge or digestate that allows the following: (1) low pressure and low temperature energy effective drying of from 10 to 40% remaining water content, (2) disinfection of pathogen (micro)organisms, (3) heavy metal reduction, (4) production of products of predetermined quality (e.g. containing different quantities of water; it can be used as a fertilizer, or if the percentage of water in the dry sludge is decreased to 10%, then the dried sludge can be used as a fuel with a calorific value similar to coal). An important feature is also the utilization of low

A comparison of aerobic granular sludge with conventional and compact biological treatment technologies.

Science.gov (United States)

Bengtsson, Simon; de Blois, Mark; Wilén, Britt-Marie; Gustavsson, David

2018-03-20

The aerobic granular sludge (AGS) technology is growing towards becoming a mature option for new municipal wastewater treatment plants and capacity extensions. A process based on AGS was compared to conventional activated sludge processes (with and without enhanced biological phosphorus removal), an integrated fixed-film activated sludge (IFAS) process and a membrane bioreactor (MBR) by estimating the land area demand (footprint), electricity demand and chemicals' consumption. The process alternatives compared included pre-settling, sludge digestion and necessary post-treatment to achieve effluent concentrations of 8 mg/L nitrogen and 0.2 mg/L phosphorus at 7°C. The alternative based on AGS was estimated to have a 40-50% smaller footprint and 23% less electricity requirement than conventional activated sludge. In relation to the other compact treatment options IFAS and MBR, the AGS process had an estimated electricity usage that was 35-70% lower. This suggests a favourable potential for processes based on AGS although more available experience of AGS operation and performance at full scale is desired.

Environmental sustainability of wastewater sludge treatments

DEFF Research Database (Denmark)

Boyer-Souchet, Florence; Larsen, Henrik Fred

treatment for municipal waste water. A special focus area in Neptune is sludge handling because the sludge amount is expected to increase due to advanced waste water treatment. The main sludge processing methods assessed in Neptune can be divided into two categories: disintegration processes before...... anaerobic digestion (thermal hydrolysis and ultrasound disintegration) and inertisation processes performed at high temperatures (incineration, pyrolysis, gasification, wet oxidation) but they all aim at volume reduction and removal of biodegradable compounds before safe sludge disposal or reuse of its...... resources. As part of a sustainability assessment (or “best practice evaluation”), a comparison between the existing and new sludge handling techniques have been done by use of life cycle assessment (LCA).The concept of induced impacts as compared to avoided impacts when introducing a new sludge treatment...

Disinfection of municipal sewage sludges in installation equipped with electron accelerator

International Nuclear Information System (INIS)

Chmielewski, A.G.; Zimek, Z.; Bryl-Sandelewska, T.; Kosmal, W.; Kalisz, L.; Kazmierczuk, M.

1995-01-01

Growing awareness of environment pollution hazards causes more and more stringent waste disposal regulations in many countries which stimulate searching for new methods of waste disposal, the best of which is recycling them after suitable treatment. Sludges from municipal sewage treatment plants contain organic and inorganic components valuable as soil fertilizer, so if disinfected they can be beneficially recycled in agriculture instead of being burdensome waste. Investigations performed in many countries showed that irradiation with a suitable dose of gamma or electron beam radiation makes sewage sludges sanitary safe and usable as soil fertilizer immediately after treatment. This paper describes some results of investigations performed in the Institute of Nuclear Chemistry and Technology and the Institute of Environmental Protection in Warsaw on the influence of 10 MeV electron beam on bacteria, parasites and parasite eggs present in sewage sludges from different municipal sewage treatment plants in Poland. Basic design parameters of the industrial installation elaborated on the basis of those experiments are presented. (Author)

Biodegradation of waste PET based copolyesters in thermophilic anaerobic sludge

Czech Academy of Sciences Publication Activity Database

Hermanová, S.; Šmejkalová, P.; Merna, J.; Zarevúcka, Marie

2015-01-01

Roč. 111, Jan (2015), s. 176-184 ISSN 0141-3910 Institutional support: RVO:61388963 Keywords : poly(ethylene terephthalate) * copolymers * sludge * biodegradation * hydrolysis * waste Subject RIV: EI - Biotechnology ; Bionics Impact factor: 3.120, year: 2015

Ultrasonic sludge disintegration for enhanced methane production in anaerobic digestion: effects of sludge hydrolysis efficiency and hydraulic retention time.

Science.gov (United States)

Kim, Dong-Jin; Lee, Jonghak

2012-01-01

Hydrolysis of waste activated sludge (WAS) has been regarded as the rate limiting step of anaerobic sludge digestion. Therefore, in this study, the effect of ultrasound and hydraulic residence time during sludge hydrolysis was investigated with the goal of enhancing methane production from anaerobic digestion (AD). WAS was ultrasonically disintegrated for hydrolysis, and it was semi-continuously fed to an anaerobic digesters at various hydraulic retention times (HRTs). The results of these experiments showed that the solids and chemical oxygen demand (COD) removal efficiencies when using ultrasonically disintegrated sludge were higher during AD than the control sludge. The longer the HRT, the higher the removal efficiencies of solids and COD, while methane production increased with lower HRT. Sludge with 30% hydrolysis produced 7 × more methane production than the control sludge. The highest methane yields were 0.350 m(3)/kg volatile solids (VS)(add) and 0.301 m(3)/kg COD(con) for 16 and 30% hydrolyzed sludge, respectively. In addition, we found that excess ultrasound irradiation may inhibit AD since the 50% hydrolyzed sludge produced lower methane yields than 16 and 30% hydrolyzed sludge.

Unified Modeling of Filtration and Expression of Biological Sludge

DEFF Research Database (Denmark)

Sørensen, Peter Borgen

Dewatering is a costly operation in both industry, e.g . when dewatering drilling mud, harbor sludge or biomass, and at municipal wastewater treatment plants when dewatering biological sludges. In practice, design and operation of dewatering equipment are mostly based on empirical knowledge, and ......, and normally results are not satisfactory, e.g. in terms of cake solids or capacity of equipment. Thus, there is a need for theoretical and technical developments to improve dewatering performance, based on better scientific knowledge and well defined principles and rules....

Radioactive contamination of sewage sludge

International Nuclear Information System (INIS)

Soeder, C.J.; Zanders, E.; Raphael, T.

1986-01-01

Because of the radioactivity released through the explosion of the nuclear reactor near Chernobyl radionuclides have been accumulated to a significant extent in sewage sludge in the Federal Republic of Germany. This is demonstrated for samples from four activated sludge plants according to a recent recommendation of the German Commission for Radiation Protection, there is until now no reason to deviate from the common practices of sludge disposal or incineration. The degree of radioactive contamination of plant materials produced on farm lands on which sewage sludge is being spread cannot be estimated with sufficient certainty yet. Additional information is required. (orig.) [de

Sewage sludge disposal in Austria

International Nuclear Information System (INIS)

Koch, F.

1997-01-01

Sewage systems serve about 70% of the Austrian population, producing 6 million m 3 of sewage sludge per year with a dry matter content of 4-5%. At present about 52% of this sludge is disposed of in land fills, 33% is incinerated, and only about 15 % is used in agriculture. Although agricultural utilization is becoming increasingly important, several problems, especially those related to public opinion, need to be resolved before increased use will be possible. In this paper, wastewater treatment and sewage-sludge production in Austria, and problems associated with sludge disposal are discussed. (author)

Sewage sludges disinfection

International Nuclear Information System (INIS)

Alexandre, D.

1977-01-01

There is an hygienic risk in using biological sewage sludges for agriculture. Systematic analysis carried out on sludges samples obtained from purification plants in East and South part of France, show the almost uniform presence of pathogenic microorganisms. Some of it survive more than 9 months after soil application. Conventional process for disinfection: liming and heat are not suitable for agricultural use. On the other hand, irradiation involves no modification in structure and composition of sludges. Radiation doses required for disinfection vary according to microorganisms. If some of them are eliminated with rather light doses (200 krad) mycobacteria, viruses and eggs of worms resist to more important doses. Security dose is estimated around 1000 krad

Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor.

Science.gov (United States)

Guerrero-Barajas, Claudia; Ordaz, Alberto; García-Solares, Selene Montserrat; Garibay-Orijel, Claudio; Bastida-González, Fernando; Zárate-Segura, Paola Berenice

2015-10-15

The importance of microbial sulfate reduction relies on the various applications that it offers in environmental biotechnology. Engineered sulfate reduction is used in industrial wastewater treatment to remove large concentrations of sulfate along with the chemical oxygen demand (COD) and heavy metals. The most common approach to the process is with anaerobic bioreactors in which sulfidogenic sludge is obtained through adaptation of predominantly methanogenic granular sludge to sulfidogenesis. This process may take a long time and does not always eliminate the competition for substrate due to the presence of methanogens in the sludge. In this work, we propose a novel approach to obtain sulfidogenic sludge in which hydrothermal vents sediments are the original source of microorganisms. The microbial community developed in the presence of sulfate and volatile fatty acids is wide enough to sustain sulfate reduction over a long period of time without exhibiting inhibition due to sulfide. This protocol describes the procedure to generate the sludge from the sediments in an upflow anaerobic sludge blanket (UASB) type of reactor. Furthermore, the protocol presents the procedure to demonstrate the capability of the sludge to remove by reductive dechlorination a model of a highly toxic organic pollutant such as trichloroethylene (TCE). The protocol is divided in three stages: (1) the formation of the sludge and the determination of its sulfate reducing activity in the UASB, (2) the experiment to remove the TCE by the sludge, and (3) the identification of microorganisms in the sludge after the TCE reduction. Although in this case the sediments were taken from a site located in Mexico, the generation of a sulfidogenic sludge by using this procedure may work if a different source of sediments is taken since marine sediments are a natural pool of microorganisms that may be enriched in sulfate reducing bacteria.

Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor

Science.gov (United States)

Guerrero-Barajas, Claudia; Ordaz, Alberto; García-Solares, Selene Montserrat; Garibay-Orijel, Claudio; Bastida-González, Fernando; Zárate-Segura, Paola Berenice

2015-01-01

The importance of microbial sulfate reduction relies on the various applications that it offers in environmental biotechnology. Engineered sulfate reduction is used in industrial wastewater treatment to remove large concentrations of sulfate along with the chemical oxygen demand (COD) and heavy metals. The most common approach to the process is with anaerobic bioreactors in which sulfidogenic sludge is obtained through adaptation of predominantly methanogenic granular sludge to sulfidogenesis. This process may take a long time and does not always eliminate the competition for substrate due to the presence of methanogens in the sludge. In this work, we propose a novel approach to obtain sulfidogenic sludge in which hydrothermal vents sediments are the original source of microorganisms. The microbial community developed in the presence of sulfate and volatile fatty acids is wide enough to sustain sulfate reduction over a long period of time without exhibiting inhibition due to sulfide. This protocol describes the procedure to generate the sludge from the sediments in an upflow anaerobic sludge blanket (UASB) type of reactor. Furthermore, the protocol presents the procedure to demonstrate the capability of the sludge to remove by reductive dechlorination a model of a highly toxic organic pollutant such as trichloroethylene (TCE). The protocol is divided in three stages: (1) the formation of the sludge and the determination of its sulfate reducing activity in the UASB, (2) the experiment to remove the TCE by the sludge, and (3) the identification of microorganisms in the sludge after the TCE reduction. Although in this case the sediments were taken from a site located in Mexico, the generation of a sulfidogenic sludge by using this procedure may work if a different source of sediments is taken since marine sediments are a natural pool of microorganisms that may be enriched in sulfate reducing bacteria. PMID:26555802

40 CFR Appendix A to Part 503 - Procedure To Determine the Annual Whole Sludge Application Rate for a Sewage Sludge

Science.gov (United States)

2010-07-01

... Whole Sludge Application Rate for a Sewage Sludge A Appendix A to Part 503 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SEWAGE SLUDGE STANDARDS FOR THE USE OR DISPOSAL OF SEWAGE SLUDGE Pt... a Sewage Sludge Section 503.13(a)(4)(ii) requires that the product of the concentration for each...

Bilevel thresholding of sliced image of sludge floc.

Science.gov (United States)

Chu, C P; Lee, D J

2004-02-15

This work examined the feasibility of employing various thresholding algorithms to determining the optimal bilevel thresholding value for estimating the geometric parameters of sludge flocs from the microtome sliced images and from the confocal laser scanning microscope images. Morphological information extracted from images depends on the bilevel thresholding value. According to the evaluation on the luminescence-inverted images and fractal curves (quadric Koch curve and Sierpinski carpet), Otsu's method yields more stable performance than other histogram-based algorithms and is chosen to obtain the porosity. The maximum convex perimeter method, however, can probe the shapes and spatial distribution of the pores among the biomass granules in real sludge flocs. A combined algorithm is recommended for probing the sludge floc structure.

Oxidation of oily sludge in supercritical water

International Nuclear Information System (INIS)

Cui Baochen; Cui Fuyi; Jing Guolin; Xu Shengli; Huo Weijing; Liu Shuzhi

2009-01-01

The oxidation of oily sludge in supercritical water is performed in a batch reactor at reaction temperatures between 663 and 723 K, the reaction times between 1 and 10 min and pressure between 23 and 27 MPa. Effect of reaction parameters such as reaction time, temperature, pressure, O 2 excess and initial COD on oxidation of oily sludge is investigated. The results indicate that chemical oxygen demand (COD) removal rate of 92% can be reached in 10 min. COD removal rate increases as the reaction time, temperature and initial COD increase. Pressure and O 2 excess have no remarkable affect on reaction. By taking into account the dependence of reaction rate on COD concentration, a global power-law rate expression was regressed from experimental data. The resulting pre-exponential factor was 8.99 x 10 14 (mol L -1 ) -0.405 s -1 ; the activation energy was 213.13 ± 1.33 kJ/mol; and the reaction order for oily sludge (based on COD) is 1.405. It was concluded that supercritical water oxidation (SCWO) is a rapidly emerging oily sludge processing technology.

Energy potential of the modified excess sludge

Science.gov (United States)

Zawieja, Iwona

2017-11-01

On the basis of the SCOD value of excess sludge it is possible to estimate an amount of energy potentially obtained during the methane fermentation process. Based on a literature review, it has been estimated that from 1 kg of SCOD it is possible to obtain 3.48 kWh of energy. Taking into account the above methane and energy ratio (i.e. 10 kWh/1Nm3 CH4), it is possible to determine the volume of methane obtained from the tested sludge. Determination of potential energy of sludge is necessary for the use of biogas as a source of power generators as cogeneration and ensure the stability of this type of system. Therefore, the aim of the study was to determine the energy potential of excess sludge subjected to the thermal and chemical disintegration. In the case of thermal disintegration, test was conducted in the low temperature 80°C. The reagent used for the chemical modification was a peracetic acid, which in an aqueous medium having strong oxidizing properties. The time of chemical modification was 6 hours. Applied dose of the reagent was 1.0 ml CH3COOOH/L of sludge. By subjecting the sludge disintegration by the test methods achieved an increase in the SCOD value of modified sludge, indicating the improvement of biodegradability along with a concomitant increase in their energy potential. The obtained experimental production of biogas from disintegrated sludge confirmed that it is possible to estimate potential intensity of its production. The SCOD value of 2576 mg O2/L, in the case of chemical disintegration, was obtained for a dose of 1.0 ml CH3COOH/L. For this dose the pH value was equal 6.85. In the case of thermal disintegration maximum SCOD value was 2246 mg O2/L obtained at 80°C and the time of preparation 6 h. It was estimated that in case of thermal disintegration as well as for the chemical disintegration for selected parameters, the potential energy for model digester of active volume of 5L was, respectively, 0.193 and 0,118 kWh.

Energy potential of the modified excess sludge

Directory of Open Access Journals (Sweden)

Zawieja Iwona

2017-01-01

Full Text Available On the basis of the SCOD value of excess sludge it is possible to estimate an amount of energy potentially obtained during the methane fermentation process. Based on a literature review, it has been estimated that from 1 kg of SCOD it is possible to obtain 3.48 kWh of energy. Taking into account the above methane and energy ratio (i.e. 10 kWh/1Nm3 CH4, it is possible to determine the volume of methane obtained from the tested sludge. Determination of potential energy of sludge is necessary for the use of biogas as a source of power generators as cogeneration and ensure the stability of this type of system. Therefore, the aim of the study was to determine the energy potential of excess sludge subjected to the thermal and chemical disintegration. In the case of thermal disintegration, test was conducted in the low temperature 80°C. The reagent used for the chemical modification was a peracetic acid, which in an aqueous medium having strong oxidizing properties. The time of chemical modification was 6 hours. Applied dose of the reagent was 1.0 ml CH3COOOH/L of sludge. By subjecting the sludge disintegration by the test methods achieved an increase in the SCOD value of modified sludge, indicating the improvement of biodegradability along with a concomitant increase in their energy potential. The obtained experimental production of biogas from disintegrated sludge confirmed that it is possible to estimate potential intensity of its production. The SCOD value of 2576 mg O2/L, in the case of chemical disintegration, was obtained for a dose of 1.0 ml CH3COOH/L. For this dose the pH value was equal 6.85. In the case of thermal disintegration maximum SCOD value was 2246 mg O2/L obtained at 80°C and the time of preparation 6 h. It was estimated that in case of thermal disintegration as well as for the chemical disintegration for selected parameters, the potential energy for model digester of active volume of 5L was, respectively, 0.193 and 0,118 kWh.

PBDEs in Italian sewage sludge and environmental risk of using sewage sludge for land application

International Nuclear Information System (INIS)

Cincinelli, Alessandra; Martellini, Tania; Misuri, Lorenza; Lanciotti, Eudes; Sweetman, Andy; Laschi, Serena; Palchetti, Ilaria

2012-01-01

Polybrominated diphenyl ethers (PBDEs) were determined in sewage sludge samples collected from eight Italian wastewater treatment plants (WWTPs) between June 2009 and March 2010. Total PBDE concentrations ranged from 158.3 to 9427 ng g −1 dw, while deca-BDE (BDE-209) (concentrations ranging from 130.6 to 9411 ng g −1 dw) dominated the congener profile in all the samples, contributing between 77% and 99.8% of total PBDE. The suitability of using a magnetic particle enzyme-linked immunoassay (ELISA) to analyse PBDEs in sewage sludge was also tested. The ELISA results, expressed as BDE-47 equivalents, were well correlated with those obtained by GC–NCI–MS, with correlation coefficients (r 2 ) of 0.899 and 0.959, depending on the extraction procedure adopted. The risk assessment of PBDEs in sewage sludge addressed to land application was calculated. PEC soil values compared to the relative PNEC soil for penta and deca-BDE suggests that there is a low risk to the soil environment. - Highlights: ► PBDEs in sewage sludge were determined in eight Italian WWTPs for the first time. ► PBDEs concentrations showed differences between the eight investigated WWTPs. ► Deca-BDE (BDE-209) was the dominant congener in all samples. ► The suitability of using ELISA method to analyse PBDEs in sewage sludge was tested. ► The risk assessment of using sewage sludge for land application was evaluated. - Determination of PBDEs in sewage sludge by GC–NCI–MS and ELISA test and risk assessment when sewage sludge is used for land application.

Thermal analysis of large diameter container (LDC) with alternate loadings of KE Basin sludge

International Nuclear Information System (INIS)

MILDON, D.T.

2003-01-01

A thermal analysis was performed to determine temperature distribution and hydrogen generation for a Large Diameter Container (LDC) having a two layer load configuration made up of a lower layer, consisting of sludge from the weasel pit, and an upper layer, consisting of the KE Basin canister sludge. For each alternate loading, the response of the LDC during shipping and storage in a T Plant cell was determined. Results for various alternate loadings were compared to the base case previously reported in SNF--9955 [Crea, 2002], 4 identical batches each with 60% floor, 40% canister sludge. Results for various cases are summarized in Table 5 and transient histories for each case are contained in figures as noted in the table. The thermal response and hydrogen generation rate of the base case bounds all alternate loadings except the third alternate loading, where 0.8 m 3 of canister sludge is loaded on the top of 1.2 m 3 of weasel pit sludge. For this case, the peak sludge temperature exceeded 100 C during shipping after 6.8 days (Note: sludge boiling does not occur in any case because the LDC pressurizes during transport and interstitial water is never saturated)

Agricultural yields of irradiated sewage sludge

International Nuclear Information System (INIS)

Magnavacca, Cecilia; Miranda, E.; Sanchez, M.

1999-01-01

Lettuce, radish and ryegrass have been used to study the nitrogen fertilization of soil by sewage sludge. The results show that the irradiated sludge improve by 15 - 30 % the production yield, compared to the non-irradiated sludge. (author)

Virological investigations on inadiated sewage sludge

International Nuclear Information System (INIS)

Epp, C.

1980-08-01

The virusinactivating activity of a Co 60 -irradiation pilot plant at Geiselbullach/Munich was to be examined. We investigated 16 impure sewage water, 15 purified sewage water, 32 raw sladge samples, 62 digested sludge samples before irradiation, 52 digested sludge samples after irradiation and 9 raw sludge samples after irradiation. We completed these investigations by adding poliovaccinevirus type 1 to the digested sludge before irradiation and by adding suspensions of pure virus in MEM + 2% FBS packed in synthetic capsules and mixtures of virus and sludge packed in synthetic capsules to the digested sludge. After the irradiation we collected the capsules and determined the virustiter. The testviruses were poliovaccinevirus type 1, poliowildvirus type 1, echovirus type 6, coxsackie-B-virus type 5, coxsackie-A-virus type 9 and adenovirus type 1. In the field trial the irradiation results were like the laboratory results assuming that the sewage sludge was homogenized enough by digestion and the solid particle concentration was not more than 3%. The D-value was 300-400 krad for enteroviruses and 700 krad for adenovirus. (orig.) [de

A review on sludge dewatering indices.

Science.gov (United States)

To, Vu Hien Phuong; Nguyen, Tien Vinh; Vigneswaran, Saravanamuth; Ngo, Huu Hao

2016-01-01

Dewatering of sludge from sewage treatment plants is proving to be a significant challenge due to the large amounts of residual sludges generated annually. In recent years, research and development have focused on improving the dewatering process in order to reduce subsequent costs of sludge management and transport. To achieve this goal, it is necessary to establish reliable indices that reflect the efficiency of sludge dewatering. However, the evaluation of sludge dewaterability is not an easy task due to the highly complex nature of sewage sludge and variations in solid-liquid separation methods. Most traditional dewatering indices fail to predict the maximum cake solids content achievable during full-scale dewatering. This paper reviews the difficulties in assessing sludge dewatering performance, and the main techniques used to evaluate dewatering performance are compared and discussed in detail. Finally, the paper suggests a new dewatering index, namely the modified centrifugal index, which is demonstrated to be an appropriate indicator for estimating the final cake solids content as well as simulating the prototype dewatering process.

Implementation of co-digestion and sludge management systems in Portugal

Energy Technology Data Exchange (ETDEWEB)

Di Berardino, Santino [INETI/DER, Lisboa (Portugal)

2006-07-01

A solution based on sludge and Olive oil mill effluent (OME) co-digestion, coupled with a management plan, has been implemented, to treat and dispose safely, the mixed residues, into the natural forest and agricultural land. The mixture of up to 25% OME to the sludge improved anaerobic degradation of phenols and fats. High density fat compounds, present in OME, enhanced aggregation, settling and acetoclastic activity of anaerobic sludge. The full scale unit, obtained by modification of a cold digester, allowed to set-up a low capital cost system. The system produced large quantity of biogas and electric energy. Anaerobic degradation of the mixture improved fertilizing properties, making feasible land application of the digested mixture. Regional plan based in Geographical Information System (GIS) selected 800 ha of adequate land area for application near the WWTP. The experience is technically and economically successful. Main incomes are provided by energy use and OME charge. Sludge application in local agriculture does not generate any income, but eliminated landfill costs and reduced transportation costs.

Effects of CeO{sub 2} nanoparticles on sludge aggregation and the role of extracellular polymeric substances – Explanation based on extended DLVO

Energy Technology Data Exchange (ETDEWEB)

You, Guoxiang [Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098 (China); College of Environment, Hohai University, Nanjing 210098 (China); Hou, Jun, E-mail: hhuhjyhj@126.com [Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098 (China); College of Environment, Hohai University, Nanjing 210098 (China); Wang, Peifang, E-mail: pfwang2005@hhu.edu.cn [Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098 (China); College of Environment, Hohai University, Nanjing 210098 (China); Xu, Yi; Wang, Chao; Miao, Lingzhan; Lv, Bowen; Yang, Yangyang; Luo, Hao [Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098 (China); College of Environment, Hohai University, Nanjing 210098 (China)

2016-11-15

The extended DLVO (XDLVO) theory was applied to elucidate the potential effects of CeO{sub 2} nanoparticles (CeO{sub 2} NPs) on sludge aggregation and the role of extracellular polymeric substances (EPS). In this study, seven different concentrations of CeO{sub 2} NPs were added to activated sludge cultured in sequencing batch reactors (SBRs) and compared with a control test that received no CeO{sub 2} NPs. After exposure to 50 mg/L CeO{sub 2} NPs, a negligible change (p>0.1) occurred in the sludge volume index (SVI), whereas the flocculability and aggregation of the sludge decreased by 18.8% and 11.2%, respectively, resulting in a high effluent turbidity. The XDLVO theory demonstrated that the adverse effects of the CeO{sub 2} NPs on sludge aggregation were due to an enhanced barrier energy. Compared to the van der Waals energies (W{sub A}) and the electric double layer (W{sub R}), the acid-base interaction (W{sub AB}) markedly changed for the various concentrations of CeO{sub 2} NPs. The EPS played a decisive role in the sludge surface characteristics, as the removal of EPS equals to the negative effects induced by 5–10 mg/L CeO{sub 2} NPs on the sludge flocculability and aggregation. The presence of CeO{sub 2} NPs induced negative contributions to the tight boundary EPS (TB-EPS) and core bacteria while positive contributions to the total interaction energy of the loose boundary EPS (LB-EPS). - Highlights: • CeO{sub 2} NPs adversely affected the flocculability and aggregation of the sludge. • The presence of CeO{sub 2} NPs increased the energy barrier and led to a stable suspension. • The removal of EPS equals to the negative effects induced by 5–10 mg/L CeO{sub 2} NPs. • The acid-base interaction was dominate and markedly changed for the CeO{sub 2} NPs. • CeO{sub 2} NPs induced negative contributions to the TB-EPS while positive to the LB-EPS.

Enhancement of sludge reduction and methane production by removing extracellular polymeric substances from waste activated sludge.

Science.gov (United States)

Nguyen, Minh Tuan; Mohd Yasin, Nazlina Haiza; Miyazaki, Toshiki; Maeda, Toshinari

2014-12-01

The management of waste activated sludge (WAS) recycling is a concern that affects the development of the future low-carbon society, particularly sludge reduction and biomass utilization. In this study, we investigated the effect of removing extracellular polymeric substances (EPS), which play important roles in the adhesion and flocculation of WAS, on increased sludge disintegration, thereby enhancing sludge reduction and methane production by anaerobic digestion. EPS removal from WAS by ethylenediaminetetraacetic acid (EDTA) significantly enhanced sludge reduction, i.e., 49 ± 5% compared with 27 ± 1% of the control at the end the digestion process. Methane production was also improved in WAS without EPS by 8881 ± 109 CH4 μmol g(-1) dry-weight of sludge. Microbial activity was determined by denaturing gradient gel electrophoresis and real-time polymerase chain reaction, which showed that the hydrolysis and acetogenesis stages were enhanced by pretreatment with 2% EDTA, with a larger methanogenic community and better methane production. Copyright © 2014 Elsevier Ltd. All rights reserved.

Comparison and analysis of membrane fouling between flocculent sludge membrane bioreactor and granular sludge membrane bioreactor.

Directory of Open Access Journals (Sweden)

Wang Jing-Feng

Full Text Available The goal of this study is to investigate the effect of inoculating granules on reducing membrane fouling. In order to evaluate the differences in performance between flocculent sludge and aerobic granular sludge in membrane reactors (MBRs, two reactors were run in parallel and various parameters related to membrane fouling were measured. The results indicated that specific resistance to the fouling layer was five times greater than that of mixed liquor sludge in the granular MBR. The floc sludge more easily formed a compact layer on the membrane surface, and increased membrane resistance. Specifically, the floc sludge had a higher moisture content, extracellular polymeric substances concentration, and negative surface charge. In contrast, aerobic granules could improve structural integrity and strength, which contributed to the preferable permeate performance. Therefore, inoculating aerobic granules in a MBR presents an effective method of reducing the membrane fouling associated with floc sludge the perspective of from the morphological characteristics of microbial aggregates.

Modeling Aspects Of Activated Sludge Processes Part I: Process Modeling Of Activated Sludge Facilitation And Sedimentation

International Nuclear Information System (INIS)

Ibrahim, H. I.; EI-Ahwany, A.H.; Ibrahim, G.

2004-01-01

Process modeling of activated sludge flocculation and sedimentation reviews consider the activated sludge floc characteristics such as: morphology viable and non-viable cell ratio density and water content, bio flocculation and its kinetics were studied considering the characteristics of bio flocculation and explaining theory of Divalent Cation Bridging which describes the major role of cations in bio flocculation. Activated sludge flocculation process modeling was studied considering mass transfer limitations from Clifft and Andrew, 1981, Benefild and Molz 1983 passing Henze 1987, until Tyagi 1996 and G. Ibrahim et aI. 2002. Models of aggregation and breakage of flocs were studied by Spicer and Pratsinis 1996,and Biggs 2002 Size distribution of floes influences mass transfer and biomass separation in the activated sludge process. Therefore, it is of primary importance to establish the role of specific process operation factors, such as sludge loading dynamic sludge age and dissolved oxygen, on this distribution with special emphasis on the formation of primary particles

Toxicity assessment of untreated/treated electroplating sludge using human and plant bioassay.

Science.gov (United States)

Orescanin, Visnja; Durgo, Ksenija; Mikelic, Ivanka Lovrencic; Halkijevic, Ivan; Kuspilic, Marin

2018-04-30

The purpose of this work was to assess the risk to the environment arising from the electroplating sludge from both chemical and toxicological point of view. Both approaches were used for the assessment of the treatment efficiency which consisted of CaO based solidification followed by thermal treatment at 400°C. The elemental composition was determined in the bulk samples and the leachates of untreated sludge. The toxicity of the leachate was determined using two human colorectal adenocarcinoma cell lines (Caco-2 and SW 480) and Hordeum vulgare L. based plant bioassay. The same toxicity tests were employed to the leachate of the treated sludge. Untreated sludge showed extremely high cytotoxic effect to both human and plant bio-system in dose-dependent manner. The percentages higher than 0.5% and 0.05% of the leachate caused significant cytotoxic effect on Caco-2 and SW 480 cells, respectively. The percentages of the leachate higher than 0.05% also showed significant toxic effect to H. vulgare L. bio-system with complete arrest of seed germination following the treatment with 100% to 5% of the leachate. The leachate of the treated sludge showed no toxicity to any of the test systems confirming the efficiency and justification of the employed procedures for the detoxification of electroplating sludge.

Production and remediation of low-sludge, simulated Purex waste glasses, 1: Effects of sludge oxide additions on melter operation

International Nuclear Information System (INIS)

Ramsey, W.G.

1993-01-01

Glass produced during the Purex 4 campaigns of the Integrated Defense Waste Processing Facility (DWPF) Melter System (IDMS) and the 774 Research Melter contained a lower fraction of sludge components than targeted by the Product Composition Control System (PCCS). Purex 4 glass was more durable than the benchmark (EA) glass, but less durable than most simulated SRS high-level waste glasses. Also, Purex 4 glass was considerably less durable than predicted by the algorithm which will be used to control production of DWPF glass. A melter run was performed using the 774 Research Melter to determine if the initial PCCS target composition determined for Purex 4 would produce acceptable glass whose durability could be accurately modeled by Hydration Thermodynamics. Reagent grade oxides and carbonates were added to Purex 4 melter feed stock to simulate a higher sludge loading. Each canister of glass produced was sampled and the composition, crystallinity, and durability was determined. This document details the melter operation and composition and crystallinity analyses

Combination of alkaline and microwave pretreatment for disintegration of meat processing wastewater sludge.

Science.gov (United States)

Erden, G

2013-01-01

Meat processing wastewater sludge has high organic content but it is very slow to degrade in biological processes. Anaerobic digestion may be a good alternative for this type of sludge when the hydrolysis, known to be the rate-limiting step of biological sludge anaerobic degradation, could be eliminated by disintegration. This investigation deals with disintegration of meat processing wastewater sludge. Microwave (MW) irradiation and combined alkaline pretreatment and MW irradiation were applied to sludge for disintegration purposes. Disintegration performance of the methods was evaluated with disintegration degree based on total and dissolved organic carbon calculations (DD(TOC)), and the solubilization of volatile solids (S(VS)) in the pretreated sludge. Optimum conditions were found to be 140 degrees C and 30 min for MW irradiation using response surface methodology (RSM) and pH = 13 for combined pretreatment. While DD(TOC) was observed as 24.6% and 54.9, S(VS) was determined as 8.54% and 42.5% for MW pretreated and combined pretreated sludge, respectively. The results clearly show that pre-conditioning of sludge with alkaline pretreatment played an important role in enhancing the disintegration efficiency of subsequent MW irradiation. Disintegration methods also affected the anaerobic biodegradability and dewaterability of sludge. An increase of 23.6% in biogas production in MW irradiated sludge was obtained, comparing to the raw sludge at the end of the 35 days of incubation. This increase was observed as 44.5% combined pretreatment application. While MW pretreatment led to a little improvement of the dewatering performance of sludge, in combined pretreatment NaOH deteriorates the sludge dewaterability.

Separation of Flue-Gas Scrubber Sludge into Marketable Products

International Nuclear Information System (INIS)

1998-01-01

The reduction of sulfur oxides from high sulfur coal burning utility companies has resulted in the production of huge quantities of wet flue-gas desulfurization scrubber sludge. A typical 400 MW power station burning a coal containing 3.5% sulfur by weight and using a limestone absorbent would produce approximately 177,000 tons (dry weight) of scrubber sludge per year. This brownish colored, finely divided material contains calcium sulfite (CaSO 3 · 1/2 H 2 O), calcium sulfate (CaSO 4 · 2H 2 O), unreacted limestone (CaCO 3 ), and various other impurities such as fly-ash and iron oxide particles. The physical separation of the components of scrubber sludge would result in the re-use of this material. The primary use would be conversion to a highly pure synthetic gypsum. This technical report concentrates on the effect of baffle configuration on the separation of calcium sulfite/sulfate from limestone. The position of the baffles as they related to the feed inlet, and the quantity of the baffles were examined. A clean calcium sulfite/sulfate (less than 2.0% limestone by weight) was achieved with the combination of water-only cyclone and horizontally baffled column

Potential impacts of using sewage sludge biochar on the growth of plant forest seedlings

Directory of Open Access Journals (Sweden)

Maria Isidoria Silva

Full Text Available ABSTRACT: Sewage sludge has long been successfully used in the production of nursery plants; however, some restriction may apply due to its high pathogenic characteristics. The process of charring the organic waste significantly reduces that undesired component and may be as effective as the non-charred residue. The aim of this study was to evaluate the effect of sewage sludge biochar on the growth and morphological traits of eucalyptus ( Eucalyptus grandis L. seedlings, and compare results with those observed when using uncharred sewage sludge. Treatments were arranged in a completely randomized design, in a 2 x 2 factorial scheme, with four replications. Charred and non-charred sewage sludge were tested with and without NPK addition. A control treatment was also evaluated. Ten weeks old eucalyptus seedlings were transferred to the pots and grew for eight weeks. Chlorophyll content, plant height and stem diameter were measured at 0, 30 and 60 days after transplant. Shoot and root biomass were measured after plant harvest. Dickson Quality Index was calculated to evaluate the overall quality of seedlings. Biochar was effective in improving the seedlings quality, and had similar effects as the non-charred waste. Therefore, sewage sludge biochar has the potential to improve the process of production of forest species seedlings and further reduce the environmental risks associated with the use of non-charred sewage sludge.

Sludge reduction by ozone: Insights and modeling of the dose-response effects.

Science.gov (United States)

Fall, C; Silva-Hernández, B C; Hooijmans, C M; Lopez-Vazquez, C M; Esparza-Soto, M; Lucero-Chávez, M; van Loosdrecht, M C M

2018-01-15

Applying ozone to the return flow in an activated sludge (AS) process is a way for reducing the residual solids production. To be able to extend the activated sludge models to the ozone-AS process, adequate prediction of the tri-atoms effects on the particulate COD fractions is needed. In this study, the biomass inactivation, COD mineralization, and solids dissolution were quantified in batch tests and dose-response models were developed as a function of the reacted ozone doses (ROD). Three kinds of model-sludge were used. S1 was a lab-cultivated synthetic sludge with two components (heterotrophs X H and X P ). S2 was a digestate of S1 almost made by the endogenous residues, X P . S3 was from a municipal activated sludge plant. The specific ozone uptake rate (SO 3 UR, mgO 3 /gCOD.h) was determined as a tool for characterizing the reactivity of the sludges. SO 3 UR increased with the X H fraction and decreased with more X P . Biomass inactivation was exponential (e -β.ROD ) as a function of the ROD doses. The percentage of solids reduction was predictable through a linear model (C Miner  + Y sol ROD), with a fixed part due to mineralization (C Miner ) and a variable part from the solubilization process. The parameters of the models, i.e. the inactivation and the dissolution yields (β, 0.008-0.029 (mgO 3 /mgCOD ini ) -1 vs Y sol , 0.5-2.8 mg COD sol /mgO 3 ) varied in magnitude, depending on the intensity of the scavenging reactions and potentially the compactness of the flocs for each sludge. Copyright © 2017 Elsevier Ltd. All rights reserved.

ISCORS ASSESSMENT OF RADIOACTIVITY IN SEWAGE SLUDGE: MODELING TO ASSESS RADIATION DOSES

Science.gov (United States)

The Interagency Steering Committee on Radiation Standards (ISCORS) has recently completed a study of the occurrence within the United States of radioactive materials in sewage sludge and sewage incineration ash. One component of that effort was an examination of the possible tran...

Behaviour of biopolymeric substances in the activated sludge of an MBR system working with high hydraulic retention time.

Science.gov (United States)

Marín, Eugenio; Pérez, Jorge I; Gómez, Miguel A

2017-10-15

This study was undertaken to analyse the activated sludge of a membrane bioreactor (MBR), the behaviour of extracellular polymeric substances (EPS) and soluble microbial products (SMP) as well as their biopolymers composition, in the activated sludge of a membrane bioreactor (MBR) and their influence on membrane fouling were analysed. For the experiment an experimental fullscale MBR working with real urban wastewater at high hydraulic retention time with a variable sludge-retention time (SRT) was used. The MBR system worked in denitrification/nitrification conformation at a constant flow rate (Q = 0.45 m 3 /h) with a recirculation flow rate of 4Q. The concentrations of SMP in the activated sludge were lower than the concentrations of EPS over the entire study, with humic substances being the main components of the two biopolymers. SMP and, more specifically, SMP carbohydrates, were the most influential biopolymers in membrane fouling, while for EPS and their components, no relation was found with fouling. The SRT and temperature were the operational variables that most influenced the SMP and EPS concentration, causing the increase of SRT and temperature a lower concentration in both biopolymers, although the effect was not the same for all the components, particularly for the EPS carbohydrates, which increased with longer SRTs. Both operational variables were also the ones most influential on the concentration of organic matter of the effluent, due to their effect on the SMP. The volatile suspended solid/total suspended solid (VSS/TSS) ratio in the activated sludge can be applied as a good indicator of the risk of membrane fouling by biopolymers in MBR systems.

Water Utility Lime Sludge Reuse – An Environmental Sorbent ...

Science.gov (United States)

Lime sludge can be used as an environmental sorbent to remove sulfur dioxide (SO2) and acid gases, by the ultra-fine CaCO3 particles, and to sequester mercury and other heavy metals, by the Natural Organic Matter and residual activated carbon. The laboratory experimental set up included a simulated flue gas preparation unit, a lab-scale wet scrubber, and a mercury analyzer system. The influent mercury concentration was based on a range from 22 surveyed power plants. The reactivity of the lime sludge sample for acid neutralization was determined using a method similar to method ASTM C1318-95. Similar experiments were conducted using reagent calcium carbonate and calcium sulfate to obtain baseline data for comparing with the lime sludge test results. The project also evaluated the techno-economic feasibility and sustainable benefits of reusing lime softening sludge. If implemented on a large scale, this transformative approach for recycling waste materials from water treatment utilities at power generation utilities for environmental cleanup can save both water and power utilities millions of dollars. Huge amounts of lime sludge waste, generated from hundreds of water treatment utilities across the U.S., is currently disposed in landfills. This project evaluated a sustainable and economically-attractive approach to the use of lime sludge waste as a valuable resource for power generation utilities.

Immobilization of radioactive waste sludge from spent fuel storage pool

International Nuclear Information System (INIS)

Pavlovic, R.; Plecas, I.

1998-01-01

In the last forty years, in FR Yugoslavia, as result of the research reactors' operation and radionuclides application in medicine, industry and agriculture, radioactive waste materials of the different categories and various levels of specific activities were generated. As a temporary solution, these radioactive waste materials are stored in the two hanger type interim storages for solid waste and some type of liquid waste packed in plastic barrels, and one of three stainless steal underground containers for other types of liquid waste. Spent fuel elements from nuclear reactors in the Vinca Institute have been temporary stored in water filled storage pool. Due to the fact that the water in the spent fuel elements storage pool have not been purified for a long time, all metallic components submerged in the water have been hardly corroded and significant amount of the sludge has been settled on the bottom of the pool. As a first step in improving spent fuel elements storage conditions and slowing down corrosion in the storage spent fuel elements pool we have decided to remove the sludge from the bottom of the pool. Although not high, but slightly radioactive, this sludge had to be treated as radioactive waste material. Some aspects of immobilisation, conditioning and storage of this sludge are presented in this paper. (author

Batch system for study of Cr(VI) Bio sorption by dried waste activated sludge

International Nuclear Information System (INIS)

Farzadkia, M.; Gholami, M.; Darvishi Cheshmeh Soltani, R.; Yaghmaeian, K.; Shams Khorramabadi, G.

2009-01-01

Activated sludge from wastewater treatment systems contains both bacteria and protozoa. The cell wall of bacteria essentially consists of various compounds, such as carboxyl, acidic polysaccharides,lipids, amino acids and other components. (Author)

Effects of municipal sewage sludge doses on the yield, some yield ...

African Journals Online (AJOL)

STORAGESEVER

2008-09-03

Sep 3, 2008 ... Whereas grain yield, which was the highest component was ... land application, many studies have been performed ... grain. Analysis of variance was used to compare treatment ... een 17.0 - 164.0 cm depending on the environmental .... municipal sewage sludge for the stabilization of soil contaminated by.

Effect Of Wood-Based Biochar And Sewage Sludge Amendments For Soil Phosphorus Availability

Directory of Open Access Journals (Sweden)

Frišták Vladimír

2015-06-01

Full Text Available This study investigated the effects of two biochars (pyrolysed wood chips and garden clippings on phosphorus (P availability in a heavy-metal contaminated soil poor in phosphorus. Short-term 14-days incubation experiments were conducted to study how applications of biochars at different rates (1 and 5 % in combination with (1:1 and without dried sewage sludge from a municipal waste water treatment plant (WWTP affected the content of soil extractable P. For P-availability analyses deionized water, calcium acetate lactate (CAL, Mehlich 3 and Olsen extraction protocols were applied. In addition, the content of total and mobile forms of potentially toxic heavy metals (PTHM was studied. Application of both biochars caused a significant decrease of PTHM available forms in sewage sludge amended soil samples. The concentration of total and available P increased with higher biochar and sewage sludge application rates.

Impact of sludge retention time on sludge characteristics and microbial community in MBR.

Science.gov (United States)

Su, Yuchun; Pan, Jill Ruhsing; Huang, Chihpin; Chang, Chialing

2011-01-01

In this study, the impact of sludge retention time (SRT) on sludge characteristics and microbial community and the effect on membrane fouling in membrane bioreactor (MBR) was investigated. The results show that MBR with longer SRT has less fouling propensity, in agreement with other studies, despite the fact that the MBR with longer SRT contained higher MLSS and smaller particle size. However, much more soluble microbial products (SMPs) were released in MBR with shorter SRT. More slime on the membrane surface was observed in MBR with shorter SRT while sludge cakes formed on the membrane surface in MBR with longer SRT. The results show that SMP contributes to the severe fouling observed in MBR with shorter SRT, which is in agreement with other studies showing that SMPs were the major foulants in MBR. Under different SRTs of operation, the bacterial community structures of the sludge obtained by use of polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) were almost identical, but those on the membrane surface differed substantially. It suggests that, although SRT has impact on sludge characteristics, it doesn't affect the microbial community in the suspension.

Nanoparticles within WWTP sludges have minimal impact on leachate quality and soil microbial community structure and function

International Nuclear Information System (INIS)

Durenkamp, Mark; Pawlett, Mark; Ritz, Karl; Harris, Jim A.; Neal, Andrew L.; McGrath, Steve P.

2016-01-01

One of the main pathways by which engineered nanoparticles (ENPs) enter the environment is through land application of waste water treatment plant (WWTP) sewage sludges. WWTP sludges, enriched with Ag and ZnO ENPs or their corresponding soluble metal salts during anaerobic digestion and subsequently mixed with soil (targeting a final concentration of 1400 and 140 mg/kg for Zn and Ag, respectively), were subjected to 6 months of ageing and leaching in lysimeter columns outdoors. Amounts of Zn and Ag leached were very low, accounting for <0.3% and <1.4% of the total Zn and Ag, respectively. No differences in total leaching rates were observed between treatments of Zn or Ag originally input to WWTP as ENP or salt forms. Phospholipid fatty acid profiling indicated a reduction in the fungal component of the soil microbial community upon metal exposure. However, overall, the leachate composition and response of the soil microbial community following addition of sewage sludge enriched either with ENPs or metal salts was very similar. - Highlights: • Adding nanoparticles (NPs) to influent of a WWTP provides a realistic exposure route. • ZnO and Ag NP and metal salt soil/sludges were aged 6 months in outdoor columns. • Amounts of Zn and Ag leached were very low in NP and metal salt treatments. • Both types of metal exposure reduced the fungal component of the soil microbial community. • Responses in NP and metal salt soil/sludges were very similar overall. - The fate and effects of ENPs are studied under realistic conditions: ENPs were added to the influent of a Waste Water Treatment Plant and the resulting sewage sludges mixed with soil in lysimeters.

Hexavalent chromium removal using aerobic activated sludge batch ...

African Journals Online (AJOL)

The following Cr(VI) removal systems were tested: activated sludge alone; activated sludge with an external electron donor (5 g/. of lactose); activated sludge with PAC addition (4 g/.); activated sludge with both PAC and lactose; and PAC alone. The results reported here showed that activated sludges are capable of ...

Electrokinetic extraction of surfactants and heavy metals from sewage sludge

International Nuclear Information System (INIS)

Ferri, Violetta; Ferro, Sergio; Martinez-Huitle, Carlos A.; De Battisti, Achille

2009-01-01

Waste management represents a quite serious problem involving aspects of remediation technologies and potential re-utilization in different fields of human activities. Of course, wastes generated in industrial activities deserve more attention because of the nature and amount of xenobiotic components, often difficult to be eliminated. However, also ordinary wastes of urban origin are drawing more and more attention, depending on the concentration of noxious substances like surfactants and some heavy metal, which may eventually require expensive disposal. In the present paper, a research has been carried out on the application of electrokinetic treatments for the abatement of the above xenobiotic components from sewage sludge generated in urban wastewater treatment plants. Experiments were carried out on a laboratory scale, in a 250 mm x 50 mm x 100 mm cell, using 250-300 g of sludge for each test and current densities between 2.4 and 5.7 mA cm -2 . As a general result, quite significant abatements of heavy-metal ions and surfactants were achieved, with relatively low energy consumption

First-order hydrothermal oxidation kinetics of digested sludge compared with raw sludge.

Science.gov (United States)

Shanableh, A; Imteaz, M

2008-09-01

This article presents an assessment of the first-order hydrothermal oxidation kinetics of a selected digested sludge at subcritical ( 374 degrees C) temperatures in the range of 250-460 degrees C. Furthermore, the results were compared with reported oxidation kinetics of raw sludge treated under identical experimental conditions. In the assessment, oxidation was considered to proceed in two steps: (1) decomposition of the particulate, or non-filterable, chemical oxygen demand (PCOD); followed by (2) ultimate oxidation and removal of the total, particulate and soluble, COD. The accumulation and removal of soluble COD (SCOD) was determined from the difference between the rates of sludge decomposition and ultimate oxidation. Using results from batch and continuous-flow hydrothermal treatment experiments, the reacting organic ingredients were separated into groups according to the ease or difficulty at which they were decomposed or removed, with Arrhenius-type activation energy levels assigned to the different groups. The analysis confirmed that within the treatment range of 75% to more than 97% COD removal, the oxidation kinetics of the digested and raw sludges were nearly identical despite differences in the proportions of their original organic ingredients. The original organic ingredients were mostly removed above 75% COD removal, and the oxidation kinetics appeared to be dominated by the removal of acetic acid, an intermediate by-product which constituted 50% to more than 80% of the remaining COD. Furthermore, the oxidation kinetics of both sludge types were consistent with reported first-order oxidation kinetics of pure acetic acid solutions. The resulting kinetic models adequately represented hydrothermal oxidation of digested sludge, in terms of COD and PCOD removals, as well as accumulation and removal of the soluble SCOD.

Electrodialytic removal of cadmium from wastewater sludge

DEFF Research Database (Denmark)

Jakobsen, M. R.; Fritt-Rasmussen, Janne; Nielsen, S.

2004-01-01

This paper presents for the first time laboratory results demonstrating electrodialytic removal of Cd from wastewater sludge, which is a method originally developed for soil remediation. During the remediation a stirred suspension of wastewater sludge was exposed to an electric dc field. The liquid....../solid (ml/g fresh sludge) ratio was between 1.4 and 2. Three experiments were performed where the sludge was suspended in distilled water, citric acid or HNO"3. The experimental conditions were otherwise identical. The Cd removal in the three experiments was 69, 70 and 67%, respectively, thus the removal...... was approximately the same. Chemical extraction experiments with acidic solutions showed that 5-10 times more Cd could be extracted from decomposed sludge than from fresh sludge. It is likely that the mobilization of Cd during decomposition of the sludge contributes to the efficient removal of Cd...

Respirometry in activated sludge

NARCIS (Netherlands)

Spanjers, H.

1993-01-01

The purpose of the study was (1) to develop a respiration meter capable of continuously measuring, using different procedures, the oxygen uptake rate of activated sludge and (2) to expand knowledge about respiration related characteristics of wastewater and activated sludge.

A

Particle Size (Sieving) and Enthalpy (Acid Calorimetry) Analysis of Single-Pull K East Basin Floor and Pit Sludges

International Nuclear Information System (INIS)

Bredt, P.R.; Delegard, C.H.; Schmidt, A.J.; Silvers, K.L.; Thornton, B.M.; Gano, S.

2000-01-01

This report presents the results of particle size analyses and calorimetry testing performed on selected single-pull sludge samples collected from the Hanford K East Basin between December 1998 and June 1999. The samples were collected as isolated cores predominantly from areas that had not been previously sampled (e.g., North Loadout Pit, Dummy Elevator Pit, Tech View Pit), or from areas in which the sludge composition had been altered since the last sampling (e.g., Weasel Pit). Particle size analyses were performed by washing wet sludge samples through a series of four sieves with openings of 250, 500, 1410, and 4000 microm. The loaded sieves were weighed before and after drying to obtain wet and dry particle size distributions. Knowledge of the particle size distribution is needed to design and predict the performance of the systems that will be used to retrieve, transport, and recover sludge. Also, sieving provides an opportunity to observe the components in the sludge. For example, during sieving of the sludge sample from the North Loadout Pit, significant quantities of organic ion exchange beads were observed. The uranium metal content and the particle size of the uranium metal in the K Basin sludge will largely determine the chemical reactivity of the sludge. In turn, the designs for the sludge handling and storage systems must be compatible with the reactivity of the sludge. Therefore, acid calorimetry was performed to estimate the uranium metal content of the sludge. For this testing, sludge samples were dissolved in nitric acid within a calibrated adiabatic calorimeter. The resulting dissolution enthalpy data were then used to discriminate between metallic uranium (minus3750 J/g in nitric acid) and uranium oxide (minus394 J/g in nitric acid). Results from this testing showed that the single-pull sludge samples contained little or no uranium metal

Pressurized Fluidized Bed Combustion of Sewage Sludge

Science.gov (United States)

Suzuki, Yoshizo; Nojima, Tomoyuki; Kakuta, Akihiko; Moritomi, Hiroshi

A conceptual design of an energy recovering system from sewage sludge was proposed. This system consists of a pressurized fluidized bed combustor, a gas turbine, and a heat exchanger for preheating of combustion air. Thermal efficiency was estimated roughly as 10-25%. In order to know the combustion characteristics of the sewage sludge under the elevated pressure condition, combustion tests of the dry and wet sewage sludge were carried out by using laboratory scale pressurized fluidized bed combustors. Combustibility of the sewage sludge was good enough and almost complete combustion was achieved in the combustion of the actual wet sludge. CO emission and NOx emission were marvelously low especially during the combustion of wet sewage sludge regardless of high volatile and nitrogen content of the sewage sludge. However, nitrous oxide (N2O) emission was very high. Hence, almost all nitrogen oxides were emitted as the form of N2O. From these combustion tests, we judged combustion of the sewage sludge with the pressurized fluidized bed combustor is suitable, and the conceptual design of the power generation system is available.

Hydrothermal Liquefaction and Upgrading of Municipal Wastewater Treatment Plant Sludge: A Preliminary Techno-Economic Analysis, Rev.1

Energy Technology Data Exchange (ETDEWEB)

Snowden-Swan, Lesley J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zhu, Yunhua [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jones, Susanne B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Elliott, Douglas C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Schmidt, Andrew J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hallen, Richard T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Billing, Justin M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hart, Todd R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fox, Samuel P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Maupin, Gary D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2016-09-01

A preliminary process model and techno-economic analysis (TEA) was completed for fuel produced from hydrothermal liquefaction (HTL) of sludge waste from a municipal wastewater treatment plant (WWTP) and subsequent biocrude upgrading. The model is adapted from previous work by Jones et al. (2014) for algae HTL, using experimental data generated in fiscal year 2015 (FY15) bench-scale HTL testing of sludge waste streams. Testing was performed on sludge samples received from Metro Vancouver’s Annacis Island WWTP (Vancouver, B.C.) as part of a collaborative project with the Water Environment and Reuse Foundation (WERF). The full set of sludge HTL testing data from this effort will be documented in a separate report to be issued by WERF. This analysis is based on limited testing data and therefore should be considered preliminary. In addition, the testing was conducted with the goal of successful operation, and therefore does not represent an optimized process. Future refinements are necessary to improve the robustness of the model, including a cross-check of modeled biocrude components with the experimental GCMS data and investigation of equipment costs most appropriate at the relatively small scales used here. Environmental sustainability metrics analysis is also needed to understand the broader impact of this technology pathway. The base case scenario for the analysis consists of 10 HTL plants, each processing 100 dry U.S. ton/day (92.4 ton/day on a dry, ash-free basis) of sludge waste and producing 234 barrel per stream day (BPSD) biocrude, feeding into a centralized biocrude upgrading facility that produces 2,020 barrel per standard day of final fuel. This scale was chosen based upon initial wastewater treatment plant data collected by PNNL’s resource assessment team from the EPA’s Clean Watersheds Needs Survey database (EPA 2015a) and a rough estimate of what the potential sludge availability might be within a 100-mile radius. In addition, we received

Hydrogen Evolution and Sludge Suspension During the Preparation of the First Batch of Sludge at the Savannah River Site

International Nuclear Information System (INIS)

Hay, M.S.; Lee, E.D.

1995-01-01

The first batch of High Level Radioactive Sludge for the Defense Waste Processing Facility is being prepared in two 4.9 million liter waste tanks. The preparation involves removing water soluble salts by washing (water addition, sludge suspension, settling and decantation). Sludge suspension is accomplished using long shafted slurry pumps that are mounted on rotating turntables. During the sludge suspension runs in 1993 and 1994, the slurry pumps' cleaning radius was determined to be less than that expected from previous determinations using synthetic sludge in a full size waste tank mockup. Hydrogen concentrations in the tanks' vapor space were monitored during the sludge suspension activities. As expected, the initial agitation of the sludge increased the hydrogen concentration, however, with the controls in place the hydrogen concentration was maintained below seven percent of the lower flammability limit

Development of a test method to access the sludge reduction potential of aquatic organisms in activated sludge

NARCIS (Netherlands)

Buijs, B.R.; Klapwijk, A.; Elissen, H.J.H.; Rulkens, W.H.

2008-01-01

This article shows the development of a quantitative sludge reduction test method, which uses the sludge consuming aquatic worm Lumbriculus variegatus (Oligochaeta, Lumbriculidae). Essential for the test are sufficient oxygen supply and the presence of a non-stirred layer of sludge for burrowing of

Impacts of Sewage Sludge in Tropical Soil: A Case Study in Brazil

International Nuclear Information System (INIS)

Bettiol, W.; Ghini, R.

2011-01-01

A long-term assay was conducted to evaluate the environmental impacts of agriculture use of sewage sludge on a tropical soil. This paper describes and discusses the results obtained by applying a interdisciplinary approach and the valuable insights gained. Experimental site was located in Jaguariuna (SP, Brazil). Multiyear comparison was developed with the application of sewage sludge obtained from wastewater treatment plants at Barueri (domestic and industrial sewage) and Franca (domestic sewage), Sao Paulo State. The treatments were control, mineral fertilization, and sewage sludge applied based on the N concentration that provides the same amount of N as in the mineral fertilization recommended for corn crop, two, four, and eight times the N recommended dosage. The results obtained indicated that the amount of sewage sludge used in agricultural areas must be calculated based on the N crop needs, and annual application must be avoided to prevent over applications.

Biodegradation of tetrabromobisphenol A in the sewage sludge process.

Science.gov (United States)

Peng, Xingxing; Wang, Zhangna; Wei, Dongyang; Huang, Qiyuan; Jia, Xiaoshan

2017-11-01

Anaerobic sewage sludge capable of rapidly degrading tetrabromobisphenol A (TBBPA) was successfully acclimated in an anaerobic reactor over 280days. During the period from 0 to 280days, the TBBPA degradation rate (DR), utilization of glucose, and VSS were monitored continuously. After 280days of acclimation, the TBBPA DR of active sludge reached 96.0% after 20days of treatment in batch experiments. Based on scanning electron microscopy (SEM) observations and denaturing gradient gel electrophoresis (DGGE) determinations, the diversity of the microorganisms after 0 and 280days in the acclimated anaerobic sewage sludge was compared. Furthermore, eleven metabolites, including 2-bromophenol, 3-bromophenol, 2,4-dibromophenol, 2,6-dibromophenol, tribromophenol and bisphenol A, were identified by gas chromatography-mass spectrometry (GC-MS). Moreover, the six primary intermediary metabolites were also well-degraded by the acclimated anaerobic sewage sludge to varying degrees. Among the six target metabolites, tribromophenol was the most preferred substrate for biodegradation via debromination. These metabolites degraded more rapidly than monobromide and bisphenol A. The biodegradation data of the intermediary metabolites exhibited a good fit to a pseudo-first-order model. Finally, based on the metabolites, metabolic pathways were proposed. In conclusion, the acclimated microbial consortia degraded TBBPA and its metabolites well under anaerobic conditions. Copyright © 2017. Published by Elsevier B.V.

The prospect of hazardous sludge reduction through gasification process

Science.gov (United States)

Hakiki, R.; Wikaningrum, T.; Kurniawan, T.

2018-01-01

Biological sludge generated from centralized industrial WWTP is classified as toxic and hazardous waste based on the Indonesian’s Government Regulation No. 101/2014. The amount of mass and volume of sludge produced have an impact in the cost to manage or to dispose. The main objective of this study is to identify the opportunity of gasification technology which can be applied to reduce hazardous sludge quantity before sending to the final disposal. This preliminary study covers the technical and economic assessment of the application of gasification process, which was a combination of lab-scale experimental results and assumptions based on prior research. The results showed that the process was quite effective in reducing the amount and volume of hazardous sludge which results in reducing the disposal costs without causing negative impact on the environment. The reduced mass are moisture and volatile carbon which are decomposed, while residues are fix carbon and other minerals which are not decomposed by thermal process. The economical simulation showed that the project will achieve payback period in 2.5 years, IRR value of 53 % and BC Ratio of 2.3. The further study in the pilot scale to obtain the more accurate design and calculations is recommended.

The presence of contaminations in sewage sludge - The current situation.

Science.gov (United States)

Fijalkowski, Krzysztof; Rorat, Agnieszka; Grobelak, Anna; Kacprzak, Malgorzata J

2017-12-01

Sewage sludge/biosolids are by-wastes of municipal and industrial wastewater treatment. As sources of nutrients (C, N, P) they are widely used in intensive farming where large supplementation of organic matter to maintain fertility and enhance crop yields is needed. However, according to the report of European Commission published in 2010, only 39% of produced sewage sludge is recycled into agriculture in the European Union. This situation occurs mainly due to the fact, that the sewage sludge may contain a dangerous volume of different contaminants. For over decades, a great deal of attention has been focused on total concentration of few heavy metals and pathogenic bacteria Salmonella and Escherichia coli. The Sewage Sludge Directive (86/278/EEC) regulates the allowable limits of Zn, Cu, Ni, Pb, Cd, Cr and Hg and pathogens and allows for recovery of sludge on land under defined sanitary and environmentally sound conditions. In this paper, a review on quality of sewage sludge based on the publications after 2010 has been presented. Nowadays there are several papers focusing on new serious threats to human health and ecosystem occurring in sewage sludge - both chemicals (such as toxic trace elements - Se, Ag, Ti; nanoparticles; polyaromatic hydrocarbons; polychlorinated biphenyl; perfluorinated surfactants, polycyclic musks, siloxanes, pesticides, phenols, sweeteners, personal care products, pharmaceuticals, benzotriazoles) and biological traits (Legionella, Yersinia, Escherichia coli O157:H7). Copyright © 2017 Elsevier Ltd. All rights reserved.

Experimental study on combustion and slagging characteristics of tannery sludge

International Nuclear Information System (INIS)

Li, Chunyu; Jiang, Xuguang; Fei, Zhenwei; Chi, Yong; Yan, Jianhua

2010-01-01

Incineration is the most reasonable technique for tannery sludge disposal. The combustion and gaseous products emission characteristics of tannery sludge were investigated in this study. Tendency of slagging for combustion residue was also investigated based on the composition and microscopic scanning analysis. The high content of volatile matters and ash in tannery sludge was discovered. It was shown that the thermal decomposition and combustion of tannery sludge mainly occurs in a temperature frame between 150 degree Celsius and 780 degree Celsius. Organic acid was determined as the most important gaseous pollutant at low temperature combustion. The combustion residue from a specially designed furnace was analyzed by X-ray diffractometer (XRD) and energy dispersion spectroscopy (EDS) microprobe coupled in a scanning electron micro-scope (SEM). There is large amount of Ca in the combustion residue, and CaO was the main inorganic composition in these residues. The tannery sludge studied in this paper has a strong tendency of slagging, and the fusion of the residue began at 900 degree Celsius in combustion. It was further discovered that almost all the zinc (Zn) in tannery sludge is volatilized at 900 degree Celsius. The degree of volatilization for heavy metals at 900 degree Celsius followed the order of Zn > Cd >Cu > Mn > Pb > Cr. Most of Cr in tannery sludge is enriched in the residue during combustion. The present study reveals that it is critical to control the combustion temperature for optimal combustion efficiency and minimization of pollutants emission. (author)

Properties of ash generated during sewage sludge combustion: A multifaceted analysis

International Nuclear Information System (INIS)

Magdziarz, Aneta; Wilk, Małgorzata; Gajek, Marcin; Nowak-Woźny, Dorota; Kopia, Agnieszka; Kalemba-Rec, Izabela; Koziński, Janusz A.

2016-01-01

This paper presents chemical properties of sewage sludge ashes required for determining their thermal characteristics. A novel approach, linking selected advanced analytical techniques with FactSage modelling, was developed and applied to obtain new information on deposit formation mechanisms that contribute to fouling and slagging. The mineral matter and fusion temperatures were investigated using a variety of analytical techniques including XRF, ICP-MS, XRD, SEM-EDX and AFT. The slagging and fouling indices were calculated and the sintering properties were predicted. The studied ashes were rich in P_2O_5, CaO, SiO_2 and Fe_2O_3, but their concentrations slightly differed. Phase analyses suggested the existence of calcium and phosphorus as main phases. Thermal behaviour of ashes was studied focusing on the mass loss, temperature peaks and thermic effects with the increasing of temperature up to 1200 °C under air atmosphere. The changes in concentration of ash compounds contributed to differences in ash fusion temperatures. FactSage thermochemical equilibrium calculations were used to predict the amount of liquid slag and solid phases, giving information about slagging properties of ashes. The general conclusion based on experimental studies is that sewage sludge ashes cause the slagging and fouling hazard while they reveal low corrosive effect. - Highlights: • Characterisation of sewage sludge ashes were given. • Transformation of inorganic components was determined using XRD and FTIR. • The ash fusion behaviour of ashes was studied experimentally. • Empirical indices were calculated indicating slagging and fouling propensities. • Thermodynamic equilibrium calculation was used.

The dissolution of metal decontamination sludges stored in tanks and their management

Energy Technology Data Exchange (ETDEWEB)

Prokopowicz, R.A.; Phillips, B. [Atomic Energy of Canada Limited, Chalk River, ON (Canada)

2011-07-01

The decontamination of stainless steel components is accomplished by the use of alkaline permanganate solutions, followed by an application of solutions of complexing agents such as citric acid or oxalic acid. Spent decontamination solutions comprising residues from both steps were combined in several waste storage tanks, where they have been in storage for several years. In those tanks, a reaction between residual permanganate and unreacted complexing agents produced sludges, consisting mainly of manganese dioxide, that reside in the tanks along with supernatant liquid. In a campaign that was conducted a few years ago, the accumulated waste solution was partially treated and disposed. This treatment consisted of decanting only the supernatant liquid and transporting it to a liquid waste treatment facility that employed a Thin Film Evaporator (TFE) to concentrate the liquid and ultimately produce a bitumen-encapsulated solidified waste form for storage. A study of treatment options for the remaining sludge is reported here. The requirement was to determine a simple means of treating the sludge using existing routine processes and equipment. This will be a significant step toward the decommissioning of the decontamination waste storage tanks. The available equipment at the liquid waste treatment facility was not designed to process sludge or slurries containing a large volume fraction of solids. Laboratory testing was carried out to find a means of dissolving the decontamination waste sludges, preferably in situ, and filtering undissolved solids to meet the feed requirements of the TFE in the liquid waste treatment facility. A concentrated citric acid solution was applied to sludge samples, without the use of externally applied mixing of the reagent and sludge. In all of the samples of actual decontamination waste sludge that were tested, a quantity of undissolved material remained after treatment with citric acid. The quantities were relatively small in volume, and

The dissolution of metal decontamination sludges stored in tanks and their management

International Nuclear Information System (INIS)

Prokopowicz, R.A.; Phillips, B.

2011-01-01

The decontamination of stainless steel components is accomplished by the use of alkaline permanganate solutions, followed by an application of solutions of complexing agents such as citric acid or oxalic acid. Spent decontamination solutions comprising residues from both steps were combined in several waste storage tanks, where they have been in storage for several years. In those tanks, a reaction between residual permanganate and unreacted complexing agents produced sludges, consisting mainly of manganese dioxide, that reside in the tanks along with supernatant liquid. In a campaign that was conducted a few years ago, the accumulated waste solution was partially treated and disposed. This treatment consisted of decanting only the supernatant liquid and transporting it to a liquid waste treatment facility that employed a Thin Film Evaporator (TFE) to concentrate the liquid and ultimately produce a bitumen-encapsulated solidified waste form for storage. A study of treatment options for the remaining sludge is reported here. The requirement was to determine a simple means of treating the sludge using existing routine processes and equipment. This will be a significant step toward the decommissioning of the decontamination waste storage tanks. The available equipment at the liquid waste treatment facility was not designed to process sludge or slurries containing a large volume fraction of solids. Laboratory testing was carried out to find a means of dissolving the decontamination waste sludges, preferably in situ, and filtering undissolved solids to meet the feed requirements of the TFE in the liquid waste treatment facility. A concentrated citric acid solution was applied to sludge samples, without the use of externally applied mixing of the reagent and sludge. In all of the samples of actual decontamination waste sludge that were tested, a quantity of undissolved material remained after treatment with citric acid. The quantities were relatively small in volume, and

Heavy metals precipitation in sewage sludge

NARCIS (Netherlands)

Marchioretto, M.M.; Rulkens, W.H.; Bruning, H.

2005-01-01

There is a great need for heavy metal removal from strongly metal-polluted sewage sludges. One of the advantages of heavy metal removal from this type of sludge is the possibility of the sludge disposal to landfill with reduced risk of metals being leached to the surface and groundwater. Another

Preliminary reduction of chromium ore using Si sludge generated in silicon wafer manufacturing process

Directory of Open Access Journals (Sweden)

Jung W.-G.

2018-01-01

Full Text Available In order to promote the recycling of by-product from Si wafer manufacturing process and to develop environment-friend and low cost process for ferrochrome alloy production, a basic study was performed on the preliminary reduction reaction between chromium ore and the Si sludge, comprised of SiC and Si particles, which is recovered from the Si wafer manufacturing process for the semiconductor and solar cell industries. Pellets were first made by mixing chromium ore, Si sludge, and some binders in the designed mixing ratios and were then treated at different temperatures in the 1116°C–1388°C range in an ambient atmosphere. Cordierite and SiO2 were confirmed to be formed in the products after the reduction. Additionally, metal particles were observed in the product with Fe, Cr, and Si components. It is found that temperatures above 1300°C are necessary for the reduction of the chromium ore by the Si sludge. The reduction ratio for Fe was evaluated quantitatively for our experimental conditions, and the proper mixing ratio was suggested for the pre-reduction of the chromium ore by the Si sludge. This study provides basic information for the production of ferrochrome alloys on the pre-reduction of chromium ore using Si sludge.

Removal of reactive dye Remazol Brilliant Blue R from aqueous solutions by using anaerobically digested sewage sludge based adsorbents

Directory of Open Access Journals (Sweden)

Özçimen Didem

2016-01-01

Full Text Available In this study, adsorbents were produced from sewage sludge via chemical and thermal activation processes. Experiments were carried out in a tubular furnace at the heating rate of 20˚C min-1 and temperature of 550 ˚C with a nitrogen flow rate of 400 mL min-1 for 1 h. Dye adsorption experiments were performed with Remazol Brilliant Blue R for its several concentrations under batch equilibrium conditions by comparing sewage sludge based adsorbents with raw material and a commercial activated carbon. Maximum adsorption capacities of carbonized sewage sludge (CSWS and activated sewage sludge (ASWS were found as 7.413 mg g-1 and 9.376 mg g-1 for 100 mg L-1 dye solution, whereas commercial activated carbon had a capacity of 11.561 mg g-1. Freundlich and Langmuir isotherms were used to explain the adsorption mechanism together with pseudo-first-order and pseudo-second-order kinetic models. Langmuir isotherm, which had adsorption capacities of 34.60 mg g-1 (CSWS and 72.99 mg g-1 (ASWS, provided better fit to the equilibrium data than that of Freundlich isotherm. Pseudo second-order, model which had adsorption capacities of 7.451 mg g-1 (CSWS and 9.319 mg g-1 (ASWS, was very favorable to explain the adsorption kinetics of the dye with high regression coefficients.

Research for waste water treatment technology with low production of excessive active sludge

Directory of Open Access Journals (Sweden)

Makisha Nikolay

2017-01-01

Full Text Available The article reflects the possibility to create a technological scheme of waste water treatment of domestic and similar type of sewage within minimal amount of excessive active sludge by means of bioreactors with immobilized feed. There are various aspects to be considered: technical, economic, social and ecological. According to the above it is strongly needed to provide a combination of proper waste water treatment, minimal sludge formation and the possibility for a further use of the sludge. One of the ways to achieve the goal above is to use an immobilized feed in the aeration tank. The necessary experiments were carried out in the department of waste water treatment and water ecology. The article includes the scheme of the facility and other parameters of the experiments, which has been carried. The combination of aerobic and anaerobic processes helps to provide proper quality of integrated biological treatment. Chambers of the aeration reactor were also equipped with the polymer feed of various structures. The sludge treatment that was also strongly needed was made by means of aerobic stabilization with the use of ejecting aeration. The results of experiment showed a good effect in both components – sewage and sludge treatment. Afterwards there was also an industrial model launched which confirmed the results of the previous stage.

Environmental Assessment of Sewage Sludge Management – Focusing on Sludge Treatment Reed Bed Systems

DEFF Research Database (Denmark)

Larsen, Julie Dam

profiles of the STRB system technology and a mechanical treatment technology, constituting a basis for decision-making in relation to choice of technology. A major part of the project involved performance of fieldwork and laboratory work. Data were collected at three Danish, well-operated STRB systems...... assessment were based on international acknowledged standards and recommendations. An attributional LCA approach was chosen, and the loadings and savings for all impact categories were normalised to people equivalents (PE) (the annual loadings and savings provided by one average person). Three sludge...... gasses CH4 and N2O were larger for mechanical dewatered sludge, the net environmental loadings provided to the impact category Climate Change by this technology (S-CEN) and the STRB system technology (S-STRB and S-SPA) ended up being equally sized (9.010-4 PE), despite of higher biological activity...

Bio-remediation of a sludge containing hydrocarbons

International Nuclear Information System (INIS)

Ayotamuno, M.J.; Okparanma, R.N.; Nweneka, E.K.; Ogaji, S.O.T.; Probert, S.D.

2007-01-01

Bio-augmentation has been used as a bio-remediation option for hydrocarbon-contaminated, oily-sludge restoration. This sludge was obtained from the Bonny-Terminal Improvement Project (BTIP) for Bonny Island, near Port Harcourt, Nigeria. Its total hydrocarbon-content (THC) was 69,372 mg/kg of sludge. Three treatment reactors (X, Y and Z) and one control reactor (A) were charged with 1500 g of oily sludge and 250 g of agricultural soil (i.e. an oily sludge to soil ratio of 6:1), the mixture homogenized and allowed to settle for seven days before various CFUs were added to reactors X, Y and Z. Reactor A did not receive any bio-preparation. The agricultural soil served both as a nutrient and a microbe carrier. With regularly scheduled mixing and watering, the THC reduction in the oily sludge varied between 40.7% and 53.2% within two weeks as well as between 63.7% and 84.5% within six weeks of applying the bio-remediation. The CFU counts of the added bio-preparation varied between 1.2 x 12 12 and 3.0 x 10 12 CFU/g of sludge and decreased to 7.0 x 10 11 CFU/g of sludge by the end of the sixth week. The pH of the degrading sludge fluctuated between 6.5 and 7.8 during the same period. When compared with the performance of the indigenous microbes in the control sample, the added bio-preparation evidently increased the THC reduction rate in the oily sludge

Sewage sludge irradiation with electrons

International Nuclear Information System (INIS)

Tauber, M.

1976-01-01

The disinfection of sewage sludge by irradiation has been discussed very intensively in the last few months. Powerful electron accelerators are now available and the main features of the irradiation of sewage sludge with fast electrons are discussed and the design parameters of such installations described. AEG-Telefunken is building an irradiation plant with a 1.5 MeV, 25 mA electron accelerator, to study the main features of electron irradiation of sewage sludge. (author)

Simultaneous fluorescent gram staining and activity assessment of activated sludge bacteria.

Science.gov (United States)

Forster, Scott; Snape, Jason R; Lappin-Scott, Hilary M; Porter, Jonathan

2002-10-01

Wastewater treatment is one of the most important commercial biotechnological processes, and yet the component bacterial populations and their associated metabolic activities are poorly understood. The novel fluorescent dye hexidium iodide allows assessment of Gram status by differential absorption through bacterial cell walls. Differentiation between gram-positive and gram-negative wastewater bacteria was achieved after flow cytometric analysis. This study shows that the relative proportions of gram-positive and gram-negative bacterial cells identified by traditional microscopy and hexidium iodide staining were not significantly different. Dual staining of cells for Gram status and activity proved effective in analyzing mixtures of cultured bacteria and wastewater populations. Levels of highly active organisms at two wastewater treatment plants, both gram positive and gram negative, ranged from 1.5% in activated sludge flocs to 16% in the activated sludge fluid. Gram-positive organisms comprised Gram status and activity within activated sludge samples over a 4-day period showed significant differences over time. This method provides a rapid, quantitative measure of Gram status linked with in situ activity within wastewater systems.

Placement of radium/barium sludges in tailings areas

International Nuclear Information System (INIS)

Murphy, K.L.; Multamaki, G.E.

1980-01-01

Currently radium is removed from uranium mining and milling effluents by the addition of barium chloride to precipitate the radium as radium/barium sulphate. The precipitate is allowed to settle in sedimentation basins prior to discharge of the effluent. The sedimentation basins are not suitable for final disposal of the sludge, and placement of the sludges in the tailings area has been proposed. The geochemical environment of fresh tailings areas was characterized as an acidic, oxidized surface zone underlain by an alkaline, reduced zone comprising the rest of the tailings. The quantity of sludge produced was estimated to be small relative to the quantity of tailings, and therefor a relatively small amount of radium would be added to the tailings disposal area by the addition of sludge. To confirm whether sludge addition affected radionuclide solubilization, laboratory leaching tests were conducted on slurries of acid leach tailings, and sludge-tailings mixtures. Radium in the (Ra,Ba)SO 4 sludge was at least as stable as radium in the tailings, and the sludge was able to absorb radium released from the tailings. The addition of sludge did not affect uranium and thorium solubilization. From these results it appears that the placement of sludge in tailings areas would not adversely affect the stability of radionuclides in the tailings or sludge. (auth)

Hydrothermal Testing of K Basin Sludge and N Reactor Fuel at Sludge Treatment Project Operating Conditions

Energy Technology Data Exchange (ETDEWEB)

Delegard, Calvin H.; Schmidt, Andrew J.; Thornton, Brenda M.

2007-03-30

The Sludge Treatment Project (STP), managed for the U. S. DOE by Fluor Hanford (FH), was created to design and operate a process to eliminate uranium metal from K Basin sludge prior to packaging for Waste Isolation Pilot Plant (WIPP). The STP process uses high temperature liquid water to accelerate the reaction, produce uranium dioxide from the uranium metal, and safely discharge the hydrogen. Under nominal process conditions, the sludge will be heated in pressurized water at 185°C for as long as 72 hours to assure the complete reaction (corrosion) of up to 0.25-inch diameter uranium metal pieces. Under contract to FH, the Pacific Northwest National Laboratory (PNNL) conducted bench-scale testing of the STP hydrothermal process in November and December 2006. Five tests (~50 ml each) were conducted in sealed, un-agitated reaction vessels under the hydrothermal conditions (e.g., 7 to 72 h at 185°C) of the STP corrosion process using radioactive sludge samples collected from the K East Basin and particles/coupons of N Reactor fuel also taken from the K Basins. The tests were designed to evaluate and understand the chemical changes that may be occurring and the effects that any changes would have on sludge rheological properties. The tests were not designed to evaluate engineering aspects of the process. The hydrothermal treatment affected the chemical and physical properties of the sludge. In each test, significant uranium compound phase changes were identified, resulting from dehydration and chemical reduction reactions. Physical properties of the sludge were significantly altered from their initial, as-settled sludge values, including, shear strength, settled density, weight percent water, and gas retention.

Anaerobic digestion of industrial activated aerobic sludge

International Nuclear Information System (INIS)

Goodloe, J.G.; Roberts, R.S.

1990-04-01

The Tennessee Eastman Company manufactures a variety of organic chemicals, plastics and fibers at their Kingsport Tennessee Facility. The wastewater generated during the manufacture of these compounds is currently treated using an activated sludge process. The objective of the project is to evaluate the economic potential of an anaerobic digestion process to convert industrial sludge at the Tennessee Eastman Company into biogas. The evaluation will require collection and analysis of experimental data on the anaerobic digestion of industrial sludge obtained from Kingsport. Although the experiments will be conducted using Tennessee Eastman sludge, these results should be also generally applicable to similar industrial sludge

Integral study of sewage sludges

International Nuclear Information System (INIS)

1994-01-01

Sewage sludges are the by-product generated during the treatment process of waste water, and they are conformed by a solid phase which origin is the accumulation of pollutant materials which has been added to water during natural and anthropogenic activities. Its handling is one of the most serious problems faced by water treatment plants which involve the production, gathering, transportation, re utilization and final disposal of sewage sludges. The main purpose of this project is to perform a technical evaluation of the process of sewage sludge irradiation for its possible application as a choice for treatment and final disposal. Irradiation with gammas from Cobalt-60 shows effectiveness in disinfestation of sewage sludges, since they reduce six times the microbial population with a 7 KGy dose. In like manners with doses of 10 KGy is possible to bring down in 70 % the concentration of organic compounds, as well as to eliminate the presence of 6 to 22 organic compounds on samples of sewage sludges. The whole content of this work is presented in six sections: Introduction, Antecedents, Methodology, Conclusions, Suggestions and Bibliography. (Author)

Sludge Lancing IBL: results and experiences in the Spanish NPP's

International Nuclear Information System (INIS)

Montoro, E.; Pozo, C. del

2014-01-01

During the operation cycle of the PWR plants, oxides deposits (sludge) generated in the secondary circuit by erosion corrosion, chemical additives, etc. Which are deposited on the tube plate of GVs, limiting their efficiency and lifespan. To reduce them, Iberdrola Engineering and Construction, together with SRA SAVAC cleaned by high-pressure water means and tele visual inspection between tubes of the GVs. After Sludge Lancing cleanings performed by 250 bar from the center line, an area of solidified sludge remaining on the tubular plate was identified. Late 2010, Iberdrola Engineering and Construction, together with SRA SAVAC developed the Inner Bundle Lancing (IBL) system, which is based on a jet of water of high pressure>500 bar directly impacting areas of hard sludge within the tube bundle to detach and break the deposits into small pieces that can be extracted from GV through a closed circuit suction. (Author)

Effect of sludge solids to mono-sodium titanate (MST) ratio on MST-treated sludge

International Nuclear Information System (INIS)

Saito, H.H.

1999-01-01

The Salt Disposition Systems Engineering Team has selected two cesium removal technologies for further development to replace the In-Tank Precipitation process: small tank tetraphenylborate (TPB) precipitation and crystalline silicotitanate (CST) ion exchange. In the CST ion exchange process, incoming salt solution from storage tanks containing entrained sludge solids is pretreated with monosodium titanate (MST) to adsorb strontium and plutonium. The resulting slurry is filtered using a cross-flow filter, with the permeate sent forward to CST ion exchange columns for cesium removal prior to conversion into Class A grout at the Saltstone Facility. The MST and sludge solids are to be sent for vitrification at the Defense Waste Processing Facility (DWPF). The High Level Waste Division (HLWD) requested that the Waste Processing Technology Section (WPTS) study varying the insoluble sludge solids to MST ratio to determine the relative impact of sludge and MST on filter performance. The purpose of this study was not for an exhaustive comprehensive search for an optimized insoluble sludge solids to monosodium titanate (MST) ratio, but as a scoping study to identify any effects of having an excess of either material. This document reports the results obtained

Composting sewage sludge

International Nuclear Information System (INIS)

Epstein, E.

1979-01-01

Sewage sludge is predominantly organic matter containing domestic and industrial wastes. The inefficiency of the waste water treatment to destroy pathogens and stabilization of odor-producing volatile organic compounds necessitates further treatment before sludge can be used as a soil amendment or fertilizer. Composting, which is the rapid biological decomposition of the sludge organic matter is an excellent method of sludge stabilization. During the process, volatile organics are decomposed and many of the pathogens destoyed. The low cost of the process and its flexibility with respect to labor and capital makes the system highly attractive to municipalities. A major problem facing large urban waste water treatment facilities is the distribution or marketing. The light weight of the material, expensive hauling costs, and low fertilizer value reduce its attractiveness to the agricultural sector. Thus, the greatest market is for horticultural purposes, sod, nurseries, greenhouses, parks, and reclamation areas. The major potential benefits of irradiating compost as a means of further disinfection are: (1) elimination of any health hazard; (2) increase of market potential, i.e., providing more market outlets to distribute the material; (3) compliance with state and federal health regulations; and (4) enhancement of the economics of composting as a result of utilizing compost in speciality products commanding a higher value

Method of treating radioactive sludge waste

International Nuclear Information System (INIS)

Shoji, Yuichi; Matsuura, Hiroyuki; Ichihashi, Toshio

1989-01-01

For removing water content from sludge wastes, filtration or steam condensation may be considered, but none of them can sufficiently reduce the water content since filtration may cause clogging and steam treatment has a limit in the condensation. In view of the above, radioactive sludge wastes are dehydrated by an electroosmotic process in a vessel and then dehydrated solid contents are solidified in the vessel. Since the sludge wastes are mainly composed o fion exchange resins and iron oxides deposited to the resins, when a DC voltage is applied to the sludges containing such solid contents, a force tending to premeate them through the fine pores in the filter is exerted to water. As a result, only water is removed while the solids are being held on the filters. Since the moving direction of water is different depending on the property of the sludges, the polarity of the electrodes may be changed depending on the nature of the sludges. Thus, volume reduction can be improved and treating conditions can be controlled easily by a simple device. (N.H.)

Electrochemical pretreatment of waste activated sludge: effect of process conditions on sludge disintegration degree and methane production.

Science.gov (United States)

Ye, Caihong; Yuan, Haiping; Dai, Xiaohu; Lou, Ziyang; Zhu, Nanwen

2016-11-01

Waste activated sludge (WAS) requires a long digestion time because of a rate-limiting hydrolysis step - the first phase of anaerobic digestion (AD). Pretreatment can be used prior to AD to facilitate the hydrolysis step and improve the efficiency of WAS digestion. This study evaluated a novel application of electrochemical (EC) technology employed as the pretreatment method prior to AD of WAS, focusing on the effect of process conditions on sludge disintegration and subsequent AD process. A superior process condition of EC pretreatment was obtained by reaction time of 30 min, electrolysis voltage of 20 V, and electrode distance of 5 cm, under which the disintegration degree of WAS ranged between 9.02% and 9.72%. In the subsequent batch AD tests, 206 mL/g volatile solid (VS) methane production in EC pretreated sludge was obtained, which was 20.47% higher than that of unpretreated sludge. The AD time was 19 days shorter for EC pretreated sludge compared to the unpretreated sludge. Additionally, the EC + AD reactor achieved 41.84% of VS removal at the end of AD. The analysis of energy consumption showed that EC pretreatment could be effective in enhancing sludge AD with reduced energy consumption when compared to other pretreatment methods.

On the influence of sewage sludge irradiation by gamma radiation on the sludge properties

International Nuclear Information System (INIS)

Hegemann, W.

1976-01-01

The gamma irradiation is a technically usable method to disinfect sewage sludge. Furthermore, the slurry properties are also improved. After 24 hours' thickening time, a significantly smaller volume of concentrated thick slurry could be removed compared to untreated sludge. On the other hand, a dilution occurs with pasteurization if the heat is introduced by steam, and the initial concentration could not be achieved again even after thickening for 24 hours. The drainability of the treated sludge was also improved by irradiation, expressed by a reduction of the specific filter resistance. The costs are essentially determined by the radiation sources used. If it is technically possible to process reactor wastes in such a manner that they can be used in slurry radiation plants, costs of 3.50-4.00 DM/m 3 treated sludge seem possible. (orig.) [de

The chemical and mechanical differences between alginate-like exopolysaccharides isolated from aerobic flocculent sludge and aerobic granular sludge

NARCIS (Netherlands)

Lin, Y. M.; Sharma, P. K.; van Loosdrecht, M. C. M.

2013-01-01

This study aimed to investigate differences in the gel matrix of aerobic granular sludge and normal aerobic flocculent sludge. From both types of sludge that fed with the same municipal sewage, the functional gel-forming exopolysaccharides, alginate-like exopolysaccharides, were isolated. These two

Plant available nitrogen from anaerobically digested sludge and septic tank sludge applied to crops grown in the tropics.

Science.gov (United States)

Sripanomtanakorn, S; Polprasert, C

2002-04-01

Agricultural land is an attractive alternative for the disposal of biosolids since it utilises the recyclable nutrients in the production of crops. In Thailand and other tropical regions, limited field-study information exists on the effect of biosolids management strategies on crop N utilisation and plant available N (PAN) of biosolids. A field study was conducted to quantify the PAN of the applied biosolids, and to evaluate the N uptake rates of some tropical crops. Sunflower (Helianthus annuus) and tomato (Lycopersicon esculentum) were chosen in this study. Two types of biosolids used were: anaerobically digested sludge and septic tank sludge. The soil is acid sulfate and is classified as Sulfic Tropaquepts with heavy clay in texture. The anaerobically digested sludge applied rates were: 0, 156 and 312 kg N ha(-1) for the sunflower plots, and 0, 586, and 1172 kg N ha(-1) for the tomato plots. The septic tank sludge applied rates were: 0, 95 and 190 kg N ha(-1) for the sunflower plots, and 0, 354 and 708 kg N ha(-1) for the tomato plots, respectively. The results indicated the feasibility of applying biosolids to grow tropical crops. The applications of the anaerobically digested sludge and the septic tank sludge resulted in the yields of sunflower seeds and tomato fruits and the plant N uptakes comparable or better than that applied with only the chemical fertiliser. The estimated PAN of the anaerobically digested sludge was about 27-42% of the sludge organic N during the growing season. For the septic tank sludge, the PAN was about 15-58% of the sludge organic N. It is interesting to observe that an increase of the rate of septic tank sludge incorporated into this heavy clay soil under the cropping system resulted in the decrease of N mineralisation rate. This situation could cause the reduction of yield and N uptake of crops.

Enhanced sludge washing evaluation plan

Energy Technology Data Exchange (ETDEWEB)

Jensen, R.D.

1994-09-01

The Tank Waste Remediation System (TWRS) Program mission is to store, treat, and immobilize highly radioactive Hanford Site waste (current and future tank waste and the strontium/cesium capsules) in an environmentally sound, safe, and cost-effective manner. The scope of the TWRS Waste Pretreatment Program is to treat tank waste and separate that waste into HLW and LLW fractions and provide additional treatment as required to feed LLW and HLW immobilization facilities. Enhanced sludge washing was chosen as the baseline process for separating Hanford tank waste sludge. Section 1.0 briefly discusses the purpose of the evaluation plan and provides the background that led to the choice of enhanced sludge washing as the baseline process. Section 2.0 provides a brief summary of the evaluation plan details. Section 3.0 discusses, in some detail, the technical work planned to support the evaluation of enhanced sludge washing. Section 4.0 briefly discusses the potential important of policy issues to the evaluation. Section 5.0 discusses the methodology to be used in the evaluation process. Section 6.0 summarizes the milestones that have been defined to complete the enhanced sludge washing evaluation and provides a summary schedule to evaluate the performance of enhanced sludge washing. References are identified in Section 7.0, and additional schedule and milestone information is provided in the appendices.

Enhanced sludge washing evaluation plan

International Nuclear Information System (INIS)

Jensen, R.D.

1994-09-01

The Tank Waste Remediation System (TWRS) Program mission is to store, treat, and immobilize highly radioactive Hanford Site waste (current and future tank waste and the strontium/cesium capsules) in an environmentally sound, safe, and cost-effective manner. The scope of the TWRS Waste Pretreatment Program is to treat tank waste and separate that waste into HLW and LLW fractions and provide additional treatment as required to feed LLW and HLW immobilization facilities. Enhanced sludge washing was chosen as the baseline process for separating Hanford tank waste sludge. Section 1.0 briefly discusses the purpose of the evaluation plan and provides the background that led to the choice of enhanced sludge washing as the baseline process. Section 2.0 provides a brief summary of the evaluation plan details. Section 3.0 discusses, in some detail, the technical work planned to support the evaluation of enhanced sludge washing. Section 4.0 briefly discusses the potential important of policy issues to the evaluation. Section 5.0 discusses the methodology to be used in the evaluation process. Section 6.0 summarizes the milestones that have been defined to complete the enhanced sludge washing evaluation and provides a summary schedule to evaluate the performance of enhanced sludge washing. References are identified in Section 7.0, and additional schedule and milestone information is provided in the appendices

Effects of sulfur on lead partitioning during sludge incineration based on experiments and thermodynamic calculations.

Science.gov (United States)

Liu, Jing-yong; Huang, Shu-jie; Sun, Shui-yu; Ning, Xun-an; He, Rui-zhe; Li, Xiao-ming; Chen, Tao; Luo, Guang-qian; Xie, Wu-ming; Wang, Yu-Jie; Zhuo, Zhong-xu; Fu, Jie-wen

2015-04-01

Experiments in a tubular furnace reactor and thermodynamic equilibrium calculations were conducted to investigate the impact of sulfur compounds on the migration of lead (Pb) during sludge incineration. Representative samples of typical sludge with and without the addition of sulfur compounds were combusted at 850 °C, and the partitioning of Pb in the solid phase (bottom ash) and gas phase (fly ash and flue gas) was quantified. The results indicate that three types of sulfur compounds (S, Na2S and Na2SO4) added to the sludge could facilitate the volatilization of Pb in the gas phase (fly ash and flue gas) into metal sulfates displacing its sulfides and some of its oxides. The effect of promoting Pb volatilization by adding Na2SO4 and Na2S was superior to that of the addition of S. In bottom ash, different metallic sulfides were found in the forms of lead sulfide, aluminosilicate minerals, and polymetallic-sulfides, which were minimally volatilized. The chemical equilibrium calculations indicated that sulfur stabilizes Pb in the form of PbSO4(s) at low temperatures (incineration process mainly depended on the gas phase reaction, the surface reaction, the volatilization of products, and the concentration of Si, Ca and Al-containing compounds in the sludge. These findings provide useful information for understanding the partitioning behavior of Pb, facilitating the development of strategies to control the volatilization of Pb during sludge incineration. Copyright © 2014 Elsevier Ltd. All rights reserved.

40 CFR 61.54 - Sludge sampling.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Sludge sampling. 61.54 Section 61.54... sampling. (a) As an alternative means for demonstrating compliance with § 61.52(b), an owner or operator... days prior to a sludge sampling test, so that he may at his option observe the test. (c) Sludge shall...

Feasibility report on criticality issues associated with storage of K Basin sludge in tanks farms

Energy Technology Data Exchange (ETDEWEB)

Vail, T.S.

1997-05-29

This feasibility study provides the technical justification for conclusions about K Basin sludge storage options. The conclusions, solely based on criticality safety considerations, depend on the treatment of the sludge. The two primary conclusions are, (1) untreated sludge must be stored in a critically safe storage tank, and (2) treated sludge (dissolution, precipitation and added neutron absorbers) can be stored in a standard Double Contained Receiver Tank (DCRT) or 241-AW-105 without future restrictions on tank operations from a criticality safety perspective.

Feasibility report on criticality issues associated with storage of K Basin sludge in tanks farms

International Nuclear Information System (INIS)

Vail, T.S.

1997-01-01

This feasibility study provides the technical justification for conclusions about K Basin sludge storage options. The conclusions, solely based on criticality safety considerations, depend on the treatment of the sludge. The two primary conclusions are, (1) untreated sludge must be stored in a critically safe storage tank, and (2) treated sludge (dissolution, precipitation and added neutron absorbers) can be stored in a standard Double Contained Receiver Tank (DCRT) or 241-AW-105 without future restrictions on tank operations from a criticality safety perspective

APPLICATION OF RESPIROMETRIC TESTS FOR ASSESSMENT OF METHANOGENIC BACTERIA ACTIVITY IN WASTEWATER SLUDGE PROCESSING

Directory of Open Access Journals (Sweden)

Małgorzata Cimochowicz-Rybicka

2013-07-01

Full Text Available Production of a methane-rich gas (‘biogas’ is contemporary popular sludges processing technology which allows to generate thermal and/or electric energy. Formal requirements issued by the European Union to promote so called renewable energy resources made these process more attractive leading to its application in WWTPs which were designed based on different sludge handling processes. Authors (as active design engineers noted that dimensioning sludge digestion chamber is usually based on SRT assessment without any emphasis on sludge characteristics. Bio-mass characteristics and the estimation of its activity with respect to methane production are of great importance, from both scientific and practical points of view, as anaerobic digestion appears to be one of crucial processes in municipal wastewater handling and disposal. The authors propose respirometric tests to estimate a biomass potential to produce ‘a biogas’ and several years’ laboratory and full scale experience proved its usefulness and reliability both as a measurement and a design tool applicable in sludge handling. Dimensioning method proposed by authors, allows to construct and optimize operation of digestion chambers based on a methanogenic activity.

Determination of phosphate phases in sewage sludge ash-based fertilizers by Raman microspectroscopy.

Science.gov (United States)

Vogel, Christian; Adam, Christian; McNaughton, Don

2013-09-01

The chemical form of phosphate phases in sewage sludge ash (SSA)-based fertilizers was determined by Raman microspectroscopy. Raman mapping with a lateral resolution of 5 × 5 μm(2) easily detected different compounds present in the fertilizers with the help of recorded reference spectra of pure substances. Quartz and aluminosilicates showed Raman bands in the range of 450-520 cm(-1). Phosphates with apatite structure and magnesium triphosphate were determined at around 960 and 980 cm(-1), respectively. Furthermore, calcium/magnesium pyrophosphates were detected in some samples.

REEMISSION OF MERCURY COMPOUNDS FROM SEWAGE SLUDGE DISPOSAL

OpenAIRE

Beata Janowska

2016-01-01

The sewage sludge disposal and cultivation methods consist in storage, agricultural use, compost production, biogas production or heat treatment. The sewage sludge production in municipal sewage sludge treatment plants in year 2013 in Poland amounted to 540.3 thousand Mg d.m. The sewage sludge for agricultural or natural use must satisfy chemical, sanitary and environmental safety requirements. The heavy metal content, including the mercury content, determines the sewage sludge disposal metho...

Factors affecting the consolidation of steam generator sludge

Energy Technology Data Exchange (ETDEWEB)

Turner, C. W.; Shamsuzzaman, K.; Tapping, R. L.

1993-02-15

It is hypothesized that sludge consolidation is promoted by chemical reactions involving the various sludge constituents, although the hardness of the final product will also depend on the total porosity. Oxidizing conditions and higher temperatures produce a harder sludge. The precipitation of Zn{sub 2}SiO{sub 4}, a potential binding agent, may also promote sludge consolidation. Several solutions to prevent sludge consolidation are suggested. (Author) 3 figs., 4 tabs., 3 refs.

Analysis of lagoon sludge characteristics for choice of treatment process

Energy Technology Data Exchange (ETDEWEB)

Park, J. H.; Hwang, D. S.; Choi, Y. D.; Lee, K. I.; Hwang, S. T.; Jung, K. J. [Korea Atomic Energy Research Institute, Taejeon (Korea)

2002-04-01

The Korea Atomic Energy Research Institute has launched a decommissioning program of uranium conversion plant. One of the important tasks in the decommissioning program is the treatment of the sludge, which was generated during operation and stored in the two ponds of the lagoon. The treatment requires the volume reduction of lagoon sludges for the low cost of the program and the conversion of the chemical forms, including uranium, for the acceptance at the final disposal site. The physical properties, such as densities, were measured and chemical compositions and radiological properties were analyzed. The denitration was a candidate process which would satisfy the requirements for sludge treatment, and the characteristics of thermal decomposition and dissolution with water were analyzed. The main compounds of the sludge were ammonium and sodium nitrate from conversion plant and calcium nitrate, calcium carbonate from Ca precipitation and impurities of the yellow cake. The content of uranium, thorium and Ra-226 was high in pond-1 and low in pond-2 because those were removed during Ca precipitation. On the base of the characteristics of the sludge and available technologies, reviewed in this study and being developed in Korea Atomic Energy Research Institute, two processes were proposed and evaluated in points of the expected technological difficulties. And the cost for treatment of sludges are estimated for both processes. 79 refs., 44 figs., 37 tabs. (Author)

Membrane bioreactor (MBR) sludge inoculation in a hybrid process scheme concept to assist overloaded conventional activated sludge (CAS) process operations.

Science.gov (United States)

Fenu, A; Roels, J; Van Damme, S; Wambecq, T; Weemaes, M; Thoeye, C; De Gueldre, G; Van De Steene, B

2012-01-01

This study analyzes the effect of inoculating membrane bioreactor (MBR) sludge in a parallel-operated overloaded conventional activated sludge (CAS) system. Modelling studies that showed the beneficial effect of this inoculation were confirmed though full scale tests. Total nitrogen (TN) removal in the CAS increased and higher nitrate formation rates were achieved. During MBR sludge inoculation, the TN removal in the CAS was proven to be dependent on MBR sludge loading. Special attention was given to the effect of inoculation on sludge quality. The MBR flocs, grown without selection pressure, were clearly distinct from the more compact flocs in the CAS system and also contained more filamentous bacteria. After inoculation the MBR flocs did not evolve into good-settling compact flocs, resulting in a decreasing sludge quality. During high flow conditions the effluent CAS contained more suspended solids. Sludge volume index, however, did not increase. Laboratory tests were held to determine the threshold volume of MBR sludge to be seeded into the CAS reactor. Above 16-30%, supernatant turbidity and scum formation increased markedly.

Characterization, Modeling and Application of Aerobic Granular Sludge for Wastewater Treatment

Science.gov (United States)

Liu, Xian-Wei; Yu, Han-Qing; Ni, Bing-Jie; Sheng, Guo-Ping

Recently extensive studies have been carried out to cultivate aerobic granular sludge worldwide, including in China. Aerobic granules, compared with conventional activated sludge flocs, are well known for their regular, dense, and strong microbial structure, good settling ability, high biomass retention, and great ability to withstand shock loadings. Studies have shown that the aerobic granules could be applied for the treatment of low- or high-strength wastewaters, simultaneous removal of organic carbon, nitrogen and phosphorus, and decomposition of toxic wastewaters. Thus, this new form of activate sludge, like anaerobic granular sludge, could be employed for the treatment of municipal and industrial wastewaters in near future. This chapter attempts to provide an up-to-date review on the definition, cultivation, characterization, modeling and application of aerobic granular sludge for biological wastewater treatment. This review outlines some important discoveries with regard to the factors affecting the formation of aerobic granular sludge, their physicochemical characteristics, as well as their microbial structure and diversity. It also summarizes the modeling of aerobic granule formation. Finally, this chapter highlights the applications of aerobic granulation technology in the biological wastewater treatment. It is concluded that the knowledge regarding aerobic granular sludge is far from complete. Although previous studies in this field have undoubtedly improved our understanding on aerobic granular sludge, it is clear that much remains to be learned about the process and that many unanswered questions still remain. One of the challenges appears to be the integration of the existing and growing scientific knowledge base with the observations and applications in practice, which this paper hopes to partially achieve.

Full-scale effects of addition of sludge from water treatment stations into processes of sewage treatment by conventional activated sludge.

Science.gov (United States)

Luiz, Marguti André; Sidney Seckler, Ferreira Filho; Passos, Piveli Roque

2018-06-01

An emerging practice for water treatment plant (WTP) sludge is its disposal in wastewater treatment plants (WWTP), an alternative that does not require the installation of sludge treatment facilities in the WTP. This practice can cause both positive and negative impacts in the WWTP processes since the WTP sludge does not have the same characteristics as domestic wastewater. This issue gives plenty of information in laboratory and pilot scales, but lacks data from full-scale studies. The main purpose of this paper is to study the impact of disposing sludge from the Rio Grande conventional WTP into the ABC WWTP, an activated sludge process facility. Both plants are located in São Paulo, Brazil, and are full-scale facilities. The WTP volumetric flow rate (4.5 m³/s) is almost three times that of WWTP (1.6 m³/s). The data used in this study came from monitoring the processes at both plants. The WWTP liquid phase treatment analysis included the variables BOD, COD, TSS, VSS, ammonia, total nitrogen, phosphorus and iron, measured at the inlet, primary effluent, mixed liquor, and effluent. For the WWTP solids treatment, the parameters tested were total and volatile solids. The performance of the WWTP process was analyzed with and without sludge addition: 'without sludge' in years 2005 and 2006 and 'with sludge' from January 2007 to March 2008. During the second period, the WTP sludge addition increased the WWTP removal efficiencies for solids (93%-96%), organic matter (92%-94% for BOD) and phosphorus (52%-88%), when compared to the period 'without sludge'. These improvements can be explained by higher feed concentrations combined to same or lower effluent concentrations in the 'with sludge' period. No critical negative impacts occurred in the sludge treatment facilities, since the treatment units absorbed the extra solids load from the WTP sludge. Copyright © 2018 Elsevier Ltd. All rights reserved.

Radioactivity of sludge in Finland in 1987

International Nuclear Information System (INIS)

Puhakainen, M.; Rahola, T.

1989-05-01

Sewage sludge from municipal wastewater treatment plants was studied to determine its radionuclide concentrations. Measurements were made to find out whether any radionuclides from the nuclear power stations at Loviisa and Olkiluoto and from hospitals and medical laboratories could be detected in sludge additional to those originating from global and Chernobyl fallout. In the treatment process of water, aluminium sulphate sludge is developed at treatment plants using surface water. This kind of sludge was measured since it also concentrates radionuclides. Fallout nuclides from the Chernobyl nuclear power station after the accident predominated in all sewage sludge samples in Finland. In 1987 six different radionuclides originating from the Chernobyl fallout were detected in sewage sludge. In spring when the snow melted and large quantities of run off water flowed into the treatment plants, the activity concentrations clearly increased, but then started decreasing again. At the end of the year the highest measured 137 Cs activity concentrations were below 1000 Bq kg -1 dry weight. The highest activity concentration in sludge originated from iodine used fro medical purposes

Effects of irradiation of sewage sludge on heavy metal bioavailability

International Nuclear Information System (INIS)

Sheppard, S.C.; Mayoh, K.R.

1986-10-01

Sewage sludges are a valuable resource to agriculture, but their use is limited by the hazards of pathogens, toxic chemicals and heavy metals. Irradiation can control the pathogens and deactivate some of the toxic chemicals. The relative cost of industrial-scale irradiation using accelerators has decreased progressively. This, coupled with the increasing necessity to recycle wastes, has led to renewed interest in irradiation of sludges. In response to this renewed interest, this report examines what is known about the effects of irradiation on the bioavailability of heavy metals. Very few studies have addressed this topic, although workers in the U.S. have claimed decreased solubility of metals in irradiated sludges. We have also briefly reviewed the general literature on sludge to gain indirect evidence on the likely effects. The scant data, often based on less than ideal experimental methodologies, show no major consistent effects of irradiation on the availability of heavy metals from sludge. The data are not sufficient to rule out such effects entirely, but the effects appear to be fairly subtle and not likely to persist beyond one growth season. 85 refs

Bio-plastic (poly-hydroxy-alkanoate) production from municipal sewage sludge in the Netherlands: a technology push or a demand driven process?

Science.gov (United States)

Bluemink, E D; van Nieuwenhuijzen, A F; Wypkema, E; Uijterlinde, C A

Valorisation of components from municipal 'waste' water and sewage sludge gets more and more attention in order to come to a circular economy by developing an efficient 'waste' to value concept. On behalf of the transition team 'Grondstoffenfabriek' ('Resource factory') a preliminary research was performed for all the Dutch water boards to assess the technical and economical feasibility of poly-hydroxy-alkanoate (PHA)-production from sewage sludge, a valuable product to produce bio-plastics. This study reveals that the production of bio-plastics from sewage sludge is feasible based on technical aspects, but not yet economically interesting, even though the selling price is relatively close to the actual PHA market price. (Selling price is in this particular case the indicative cost effective selling price. The cost effective selling price covers only the total production costs of the product.) Future process optimization (maximizing the volatile fatty acids production, PHA storage capacity, etc.) and market developments are needed and will result in cost reductions of the various sub-processes. PHA-production from sewage sludge at this stage is just a technology; every further research is needed to incorporate the backward integration approach, taking into account the market demand including associated product quality aspects.

Nitrate control strategies in an activated sludge wastewater treatment process

Energy Technology Data Exchange (ETDEWEB)

Shen, Wenhao; Tao, Erpan; Chen, Xiaoquan; Liu, Dawei [South China University of Technology, Guangzhou (China); Liu, Hongbin [Kyung Hee University, Yongin (Korea, Republic of)

2014-03-15

We studied nitrate control strategies in an activated sludge wastewater treatment process (WWTP) based on the activated sludge model. Two control strategies, back propagation for proportional-integral-derivative (BP-PID) and adaptive-network based fuzzy inference systems (ANFIS), are applied in the WWTP. The simulation results show that the simple local constant setpoint control has poor control effects on the nitrate concentration control. However, the ANFIS (4*1) controller, which considers not only the local constant setpoint control of the nitrate concentration, but also three important indices in the effluent--ammonia concentration, total suspended sludge concentration and total nitrogen concentration--demonstrates good control performance. The results also prove that ANFIS (4*1) controller has better control performance than that of the controllers PI, BP-PID and ANFIS (2*1), and that the ANFIS (4*1) controller is effective in improving the effluent quality and maintaining the stability of the effluent quality.

Fiscal year 1993 1/25-scale sludge mobilization testing

International Nuclear Information System (INIS)

Powell, M.R.; Golcar, G.R.; Hymas, C.R.; McKay, R.L.

1995-04-01

Sixteen 1/25-scale sludge mobilization experiments were conducted in fiscal year (FY) 1993. The results of this testing are presented in this document. The ability of a single, centrally-located, scale model mixer pump to resuspend a layer of simulated tank sludge was evaluated for five different simulant types. The resistance of these simulants to the mobilizing action of the mixer pump jets was not found to adequately correlate with simulant vane shear strength. The data indicate that the simulant cohesion, as quantified by tensile strength, may provide a good measure of mobilization resistance. A single test was done to evaluate whether indexed mixer pump rotation is significantly more effective than the planned continuous oscillation. No significant difference was found in the sludge mobilization caused by these two modes of operation. Two tests were conducted using a clay-based sludge simulant that contained approximately 5 wt% soluble solids. The distance to which the mixer pump jets were effective for this simulant was approximately 50% greater than on similar simulants that did not contain soluble solids. The implication is that sludge dissolution effects may significantly enhance the performance of mixer pumps in some tanks. The development of a means to correlate the magnitude of this effect with waste properties is a direction for future work. Two tests were performed with the goal of determining whether the 1/25-scale sludge mobilization data can be scaled linearly to 1/12-scale. The two 1/25-scale tests were conducted using the same simulant recipe as had been used in previous 1/12-scale tests. The difficulty of matching the 1/25-scale simulants, with those used previously is thought to have adversely affected the results. Further tests are needed to determine whether the data from sludge mobilization tests can be linearly scaled

Supplementary information on K-Basin sludges

International Nuclear Information System (INIS)

MAKENAS, B.J.

1999-01-01

Three previous documents in this series have been published covering the analysis of: K East Basin Floor and Pit Sludge, K East Basin Canister Sludge, and K West Basin Canister Sludge. Since their publication, additional data have been acquired and analyses performed. It is the purpose of this volume to summarize the additional insights gained in the interim time period

Effects of wastewater sludge and its detergents on the stability of rotavirus

Energy Technology Data Exchange (ETDEWEB)

Ward, R.L. (Sandia Labs., Albuquerque, NM); Ashley, C.S.

1980-06-01

Wastewater sludge reduced the heat required to inactivate rotavirus SA-11, and ionic detergents were identified as the sludge components responsible for this effect. A similar result was found previously with reovirus. The quantitative effects of individual ionic detergents on rotavirus and reovirus were very different, and rotavirus was found to be extremely sensitive to several of these detergents. However, neither virus was destabilized by nonionic detergents. On the contrary, rotavirus was stabilized by a nonionic detergent against the potent destabilizing effects of the ionic detergent sodium dodecyl sulfate. The destabilizing effects of both cationic and anionic detergents on rotavirus were greatly altered by changes in the pH of the medium.

Fast pyrolysis of lignin, macroalgae and sewage sludge

Energy Technology Data Exchange (ETDEWEB)

Trinh, N.T.

2013-04-15

macronutrients as N, P, K, S, Mg and Ca and this could make the chars most valuable as raw materials for fertilizer production. The sewage sludge waste bulk volume (the char compared to the sludge) was reduced with 52 % by pyrolysis at 575 deg. C. It is seen that the fast pyrolysis process provides a promising method to reduce cost for landfilling and produce a bio-oil that can be used as a fuel. The pyrolysis temperature has a considerable effect on the product distributions of the lignin and sewage sludge PCR pyrolysis, as well as their bio-oil properties with respect to molecular mass distribution, identified GC-MS component compositions, water-insoluble fraction, viscosity, and HHV. A maximum of organic oil yields of lignin and sewage sludge PCR pyrolysis were obtained at optimal temperatures of 550 - 575 deg. C. In this work, the behaviors of slurry samples of wood, char and grinded char with respect to phase transitions, rheological properties, elemental composition, and energy density were investigated. Also pumping properties were investigated at temperatures of 25, 40 and 60 deg. C and the solids loading of 0 - 20 wt%. The bioslurries obtained a volume energy density of 21-23 GJ/m{sup 3} and an energy densification factor of 4.5 - 5 (when compared to beech wood). Their apparent viscosities were significantly influenced by the solid loading levels (0 - 20 wt %) and temperatures (25 - 60 deg. C). The slurry samples with 10 wt% char (having d80 of 276 {mu}m) and 20 wt% grinded char (having d80 of 118 {mu}m) were successfully pumped into a pressurized chamber (0 - 6 bar). (LN)

Separation, Characterization and Fouling Potential of Sludge Waters from Different Biological Wastewater Treatment Processes

KAUST Repository

Xue, Jinkai

2011-07-01

The major limitation, which hinders the wider application of membrane technology and increases the operating costs of membranes involved in wastewater treatment plants, is membrane fouling induced by organic matter. Extracellular polymeric products (EPS) and soluble microbial products (SMP) are the two most mentioned major foulants in publications, for which the debate on precise definitions seems to be endless. Therefore, a concept of sludge water, which conceptually covers both EPS and SMP, has been developed in this research. A standard procedure of sludge water separation, which is centrifugation at 4000g for 15 min followed by 1.2μm glass fiber filter filtration, was established based on separation experiments with membrane tank sludge from the KAUST MBR wastewater treatment plant. Afterwards, sludge waters from the KAUST MBR WWTP anoxic tank, aerobic tank and membrane tank as well as sludge waters from the Jeddah WWTP anoxic tank, aerobic tank and secondary effluent were produced through the previously developed standard procedure. The obtained sludge water samples were thereafter characterized with TOC/COD, LC-­‐OCD and F-­‐EEM, which showed that KAUST anoxic/ aerobic /membrane tank sludge waters had similar characteristics for all investigated parameters, yet the influent naturally had a higher DOC and biopolymer concentration. Moreover, lower TOC/COD, negligible biopolymers and low levels of humics were found in KAUST effluent. Compared with the KAUST MBR WWTP, the Jeddah WWTP’s sludge waters generally had higher DOC and biopolymer concentrations. To investigate sludge water fouling potential, the KAUST membrane tank sludge water as well as the Jeddah secondary effluent were filtrated through a membrane array consisting of an ultrafiltration (UF) Millipore RC10kDa at the first step followed by a nanofiltration (NF) KOCH Acid/Base stable NF200 at the second step. It was found that cake layer and standard blocking occurred simultaneously during both

Phosphorous removal from aqueous solution can be enhanced through the calcination of lime sludge.

Science.gov (United States)

Bal Krishna, K C; Niaz, Mohamed R; Sarker, Dipok C; Jansen, Troy

2017-09-15

Water treatment plants generate an enormous amount of the sludge which is normally treated as waste. In the recent past, many investigations have been focused on developing an economical adsorbent using water treatment sludge to remove phosphorous (P) from aqueous solutions. However, the great extents of the studies have been limited in the use of alum- and iron-based sludges. This study, therefore, investigated the P removal performance of the calcined lime sludge. Calcined lime sludge at 700 °C significantly enhanced the P removal efficiency whereas marginal improvement was noted when the sludge calcined at 400 °C was tested. With increase P removal efficiency, final pH values of the solution also significantly increased. P removal efficiency of the calcined sludge decreased with increasing the initial P concentrations. However, the removal efficiency could be improved by increasing the weight of the sludge. Further analysis demonstrated that P removal trend followed both pseudo-second order and diffusion-chemisorption kinetics signifying the P removal is potentially due to a multi-mechanistic reaction in which, the process is controlled by intra-particle diffusion followed by chemisorptions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Treatment and disposal of refinery sludges: Indian scenario.

Science.gov (United States)

Bhattacharyya, J K; Shekdar, A V

2003-06-01

Crude oil is a major source of energy and feedstock for petrochemicals. Oily sludge, bio-sludge and chemical sludge are the major sludges generated from the processes and effluent treatment plants of the refineries engaged in crude oil refining operations. Refineries in India generate about 28,220 tons of sludge per annum. Various types of pollutants like phenols, heavy metals, etc. are present in the sludges and they are treated as hazardous waste. Oily sludge, which is generated in much higher amount compared to other sludges, contains phenol (90-100 mg/kg), nickel (17-25 mg/kg), chromium (27-80 mg/kg), zinc (7-80 mg/kg), manganese (19-24 mg/kg), cadmium (0.8-2 mg/kg), copper (32-120 mg/kg) and lead (0.001-0.12 mg/ kg). Uncontrolled disposal practices of sludges in India cause degradation of environmental and depreciation of aesthetic quality. Environmental impact due to improper sludge management has also been identified. Salient features of various treatment and disposal practices have been discussed. Findings of a case study undertaken by the authors for Numaligarh Refinery in India have been presented. Various system alternatives have been identified for waste management in Numaligarh Refinery. A ranking exercise has been carried out to evaluate the alternatives and select the appropriate one. A detailed design of the selected waste management system has been presented.

Environmental consequences of the placement of radium-barium sludge in tailings areas

International Nuclear Information System (INIS)

Huck, P.M.; Brown, J.R.; Multimaki, G.; Murphy, K.L.

1982-01-01

A preliminary evaluation was made of the implications of placing radium-barium sludge in tailings areas. The study was restricted to a consideration of possible increases in the quantities of radionuclides escaping to the environment through either groundwater or surface water, considering the types of tailings treated and the effluent treatment systems currently operating in Canada. It was concluded that the placement of radium/barium sludge in tailings areas should not adversely affect the long-term stability of the radionuclides in the tailings or sludge, based on geochemical inorganic reactions

Performance of a system with full- and pilot-scale sludge drying reed bed units treating septic tank sludge in Brazil.

Science.gov (United States)

Calderón-Vallejo, Luisa Fernanda; Andrade, Cynthia Franco; Manjate, Elias Sete; Madera-Parra, Carlos Arturo; von Sperling, Marcos

2015-01-01

This study investigated the performance of sludge drying reed beds (SDRB) at full- and pilot-scale treating sludge from septic tanks in the city of Belo Horizonte, Brazil. The treatment units, planted with Cynodon spp., were based on an adaptation of the first-stage of the French vertical-flow constructed wetland, originally developed for treating sewage. Two different operational phases were investigated; in the first one, the full-scale unit was used together with six pilot-scale columns in order to test different feeding strategies. For the second phase, only the full-scale unit was used, including a recirculation of the filtered effluent (percolate) to one of the units of the French vertical wetland. Sludge application was done once a week emptying a full truck, during 25 weeks. The sludge was predominantly diluted, leading to low solids loading rates (median values of 18 kgTS m(-2) year(-1)). Chemical oxygen demand removal efficiency in the full-scale unit was reasonable (median of 71%), but the total solids removal was only moderate (median of 44%) in the full-scale unit without recirculation. Recirculation did not bring substantial improvements in the overall performance. The other loading conditions implemented in the pilot columns also did not show statistically different performances.

Revegetation of mined land using waste water sludge

Energy Technology Data Exchange (ETDEWEB)

Sopper, W E; Kerr, N

1980-01-01

The benefits of using sludge to reclaim land that has been used for strip mining is explained. Pennsylvania State University developed demonstration plots and used various types of sludges to illustrate this. One application of sludge is sufficient to supply plant nutrients for 3-5 years. After sludge application and incorporation, the site was broadcast seeded with grasses and legumes. Other trials and their results are noted. All show no detrimental effects on vegetation, the soil or groundwater quality due to sludge application.

Assessment of Jet Erosion for Potential Post-Retrieval K-Basin Settled Sludge

Energy Technology Data Exchange (ETDEWEB)

Wells, Beric E.; Enderlin, Carl W.; Gauglitz, Phillip A.; Peterson, Reid A.

2009-09-29

Packaged K-Basin sludge will be transported to the T Plant on the Hanford Site where it will be interim stored. The sludge will be retrieved from the storage containers and processed for disposal. A sample of high uranium content canister sludge, designated 96-13, "self-cemented" during laboratory storage. This sample was uncharacteristically strong compared to expected K-Basin material. The purpose for this work is to evaluate the potential retrieval of such sludge after storage at the T Plant via jet erosion. The specific objectives of this report are to determine the modes of erosion and the methods used to measure/assess the erodibility parameters of sludge and identify those parameters applicable to jet erosion. The erodibility parameters of sample 96-13 are characterized to the extent possible. These objectives have been met based on literature review, past experience at Pacific Northwest National Laboratory, and observation of sample 96-13 video during hot-cell activities.

Gravity Drainage of Activated Sludge on Reed Beds

DEFF Research Database (Denmark)

Christensen, Morten Lykkegaard; Dominiak, Dominik Marek; Keiding, Kristian

and operation of reed beds and the efficiencies are often lower than predicted. One reason is that the sludge quality varies from plant to plant and even within plants from time to time. No good method exists for measuring the sludge quality with respect to drainage characteristics. A new experimental method...... has therefore been developed to measure relevant quality parameters: specific cake resistance, settling velocity and cake compressibility. It has been found that activated sludge form highly compressible cake even at the low compressive pressures obtained during drainage. Numerical simulation shows......Activated sludge is a by-product from waste water treatment plants, and the water content in the sludge is high (> 90%). Among several methods to remove the water, sludge drying reed beds are often used to dewater the sludge by drainage. There is, however, no well-defined criterion for design...

Activated sludge model No. 2d, ASM2d

DEFF Research Database (Denmark)

Henze, M.

1999-01-01

The Activated Sludge Model No. 2d (ASM2d) presents a model for biological phosphorus removal with simultaneous nitrification-denitrification in activated sludge systems. ASM2d is based on ASM2 and is expanded to include the denitrifying activity of the phosphorus accumulating organisms (PAOs......). This extension of ASM2 allows for improved modeling of the processes, especially with respect to the dynamics of nitrate and phosphate. (C) 1999 IAWQ Published by Elsevier Science Ltd. All rights reserved....

Soil application of sewage sludge stabilized with steelmaking slag and its effect on soil properties and wheat growth.

Science.gov (United States)

Samara, Eftihia; Matsi, Theodora; Balidakis, Athanasios

2017-10-01

The effect of sewage sludge, stabilized with steelmaking slag, on soil chemical properties and fertility and on wheat (Triticum aestivum L.) growth was evaluated. Dewatered sewage sludge [75% (wet weight basis)] stabilized with steelmaking slag (25%) and three soils with different pH values were used in a pot experiment with winter wheat. The following treatments were applied: (i) sludge addition of 30gkg -1 (≈ 120Mgha -1 , rate equivalent to the common inorganic N fertilization for wheat, based on sludge's water soluble NO 3 -N), (ii) sludge addition of 10gkg -1 (≈ 40Mgha -1 , rate equivalent to the common inorganic N fertilization for wheat, based on sludge's Kjeldahl-N), (iii) addition of the common inorganic N fertilization for wheat (120kgNha -1 ) as NH 4 NO 3 , (iv) control (no fertilizer, no sludge). Sludge application at both rates to all soils resulted in a significant increase of pH, electrical conductivity of the saturation extract (EC se ) and soil available NO 3 -N and P, in comparison to the other two treatments and this increase remained constant till the end of the pot experiment. In sludge treatments pH did not exceed the critical value of 8.5, whereas EC se , although it did not reach the limit of 4dSm -1 , exceeded the value of 2dSm -1 at the rate of 30gkg -1 . Concentrations of heavy metals, which regulate the agronomic use of sewage sludge according to the established legislation, ranged from not detectable to lower than the respective permissible levels. Both rates of sludge's addition in all soils improved wheat's growth, as judged by the significant increase of the aboveground biomass yield and the total plant uptake of almost all nutrients, compared to the other two treatments. It was concluded that sewage sludge stabilized with steelmaking slag could be used in agriculture, applied at rates based on sludge's Kjeldahl-N content and crop's demand for N. However, potential environmental impacts must also be considered. Copyright © 2017

Attributes of the soil fertilized with sewage sludge and calcium and magnesium silicate

Directory of Open Access Journals (Sweden)

Geraldo R. Zuba Junio

2015-11-01

Full Text Available ABSTRACTThis study aimed to evaluate the chemical attributes of an Inceptisol cultivated with castor bean (Ricinus communis L., variety ‘BRS Energia’, fertilized with sewage sludge compost and calcium (Ca and magnesium (Mg silicate. The experiment was conducted at the ICA/UFMG, in a randomized block design, using a 2 x 4 factorial scheme with three replicates, and the treatments consisted of two doses of Ca-Mg silicate (0 and 1 t ha-1 and four doses of sewage sludge compost (0, 23.81, 47.62 and 71.43 t ha-1, on dry basis. Soil organic matter (OM, pH, sum of bases (SB, effective cation exchange capacity (CEC(t, total cation exchange capacity (CEC(T, base saturation (V% and potential acidity (H + Al were evaluated. There were no significant interactions between doses of sewage sludge compost and doses of Ca-Mg silicate on soil attributes, and no effect of silicate fertilization on these attributes. However, fertilization with sewage sludge compost promoted reduction in pH and increase in H + Al, OM and CEC. The dose of 71.43 t ha-1 of sewage sludge compost promoted the best soil chemical conditions.

K Basin Sludge Conditioning Testing. Nitric Acid Dissolution Testing of K East Area Sludge Composite, Small- and Large-Scale Testing

International Nuclear Information System (INIS)

Carlson, C.D.; Delegard, C.H.; Burgeson, I.E.; Schmidt, A.J.; Silvers, K.L.

1998-01-01

This report describes work performed by Pacific Northwest National Laboratory (PNNL) for Numatec Hanford Corporation (NHC) to support the development of the K Basin Sludge Treatment System. For this work, testing was performed to examine the dissolution behavior of a K East Basin floor and Weasel Pit sludge composite, referred to as K East area sludge composite, in nitric acid at the following concentrations: 2 M, 4 M, 6 M and 7.8 M. With the exception of one high solids loading test the nitric acid was added at 4X the stoichiometric requirement (assuming 100% of the sludge was uranium metal). The dissolution tests were conducted at boiling temperatures for 24 hours. Most of the tests were conducted with approximately2.5 g of sludge (dry basis). The high solids loading test was conducted with approximately7 g of sludge. A large-scale dissolution test was conducted with 26.5 g of sludge and 620 mL of 6 M nitric acid. The objectives of this test were to (1) generate a sufficient quantity of acid-insoluble residual solids for use in leaching studies, and (2) examine the dissolution behavior of the sludge composite at a larger scale

Relationship between organic matter humification and bioavailability of sludge-borne copper and cadmium during long-term sludge amendment to soil

Energy Technology Data Exchange (ETDEWEB)

Liu, Hongtao, E-mail: liuht@igsnrr.ac.cn

2016-10-01

Recycling of sludge as soil amendment poses certain risk of heavy metals contamination. This study investigated the relationship between organic matter in composted sludge and its heavy metals bioavailability over 7 years. Periodic monitoring indicated a gradual increase in organic matter degradation, accompanied by changing degrees of polymerization, i.e., ratio of humic acid (HA)/fulvic acid (FA) coupled with incremental exchangeable fraction of copper (Cu) in sludge, with a growing rate of 74.7%, rather than that in soil. However, cadmium (Cd) in composted sludge exhibited an independent manner. Linear-regression analysis revealed that the total proportion of the Cu active fraction (exchangeable plus carbonate bound) was better correlated with the degree of polymerization (DP) and humification ratio (HR) than the degradation ratio of organic matter. Overall, amount of uptaken Cu was more dependent on the humification degree of organic matter, especially the proportion of HA in humus. - Highlights: • Organic matter in sludge degraded with time goes after sludge was recycled to soil. • DP in sludge is well coupled with incremental uptaken fraction of its borne copper. • Profiles of Cadmium fractions in sludge exhibit an independent manner.

Sludge Water Characteristics Under Different Separation Methods from a Membrane Bioreactor

KAUST Repository

Wei, Chunhai

2013-11-22

The concept of sludge water was proposed to integrate the relative terminologies and its characteristics under different separation methods from a membrane bioreactor (MBR) were investigated in this study. Based on chemical oxygen demand (COD) and three-dimensional fluorescence excitation-emission matrix (F-EEM), and compared with the control (gravitational sedimentation), some suspended particulate organics or biopolymer clusters (mainly proteins) were released from sludge flocs into the supernatant after centrifugation under low to middle centrifugal forces (10-4000 g) and then aggregated into a pellet under high centrifugal forces (10000-20000 g). Filtration (1.2 μm glass fiber filter) produced sludge water with a lower biopolymers concentration than the control (gravitational sedimentation followed by filtration) due to cake layer formation during filtration. As for centrifugation followed by filtration, low to middle centrifugal forces did not significantly affect sludge water characteristics but high centrifugal forces reduced the concentrations of some proteins in sludge water from advanced analytical protocols including F-EEM and liquid chromatography with on-line organic carbon detection (LC-OCD), demonstrating a low to middle centrifugal force suitable for MBR sludge water separation. From LC-OCD, the main fractions of sludge water were humic substances and building blocks, low molecular weight neutrals and biopolymers (mainly proteins rather than polysaccharides). Supplemental materials are available for this article. Go to the publisher\\'s online edition of Separation Science and Technology to view the supplemental file. © 2013 Copyright Taylor and Francis Group, LLC.

Sludge Water Characteristics Under Different Separation Methods from a Membrane Bioreactor

KAUST Repository

Wei, Chunhai; Amy, Gary L.

2013-01-01

The concept of sludge water was proposed to integrate the relative terminologies and its characteristics under different separation methods from a membrane bioreactor (MBR) were investigated in this study. Based on chemical oxygen demand (COD) and three-dimensional fluorescence excitation-emission matrix (F-EEM), and compared with the control (gravitational sedimentation), some suspended particulate organics or biopolymer clusters (mainly proteins) were released from sludge flocs into the supernatant after centrifugation under low to middle centrifugal forces (10-4000 g) and then aggregated into a pellet under high centrifugal forces (10000-20000 g). Filtration (1.2 μm glass fiber filter) produced sludge water with a lower biopolymers concentration than the control (gravitational sedimentation followed by filtration) due to cake layer formation during filtration. As for centrifugation followed by filtration, low to middle centrifugal forces did not significantly affect sludge water characteristics but high centrifugal forces reduced the concentrations of some proteins in sludge water from advanced analytical protocols including F-EEM and liquid chromatography with on-line organic carbon detection (LC-OCD), demonstrating a low to middle centrifugal force suitable for MBR sludge water separation. From LC-OCD, the main fractions of sludge water were humic substances and building blocks, low molecular weight neutrals and biopolymers (mainly proteins rather than polysaccharides). Supplemental materials are available for this article. Go to the publisher's online edition of Separation Science and Technology to view the supplemental file. © 2013 Copyright Taylor and Francis Group, LLC.

Fermentation and chemical treatment of pulp and paper mill sludge

Science.gov (United States)

Lee, Yoon Y; Wang, Wei; Kang, Li

2014-12-02

A method of chemically treating partially de-ashed pulp and/or paper mill sludge to obtain products of value comprising taking a sample of primary sludge from a Kraft paper mill process, partially de-ashing the primary sludge by physical means, and further treating the primary sludge to obtain the products of value, including further treating the resulting sludge and using the resulting sludge as a substrate to produce cellulase in an efficient manner using the resulting sludge as the only carbon source and mixtures of inorganic salts as the primary nitrogen source, and including further treating the resulting sludge and using the resulting sludge to produce ethanol.

Technology for improving sludge concentration; Odei noshukusei kaizen gijutsu

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-03-10

Sludge generating in a sewage treatment plant is disposed through the processes such as concentration, dehydration, and incineration in sludge disposal facilities. In recent years, there has been a trend that this sludge increases in volume as well as worsens in the concentration. A case is predictable where the sludge load to the dehydrating process is so large that the sludge can no longer be processed in sufficient quantity. In the meantime, if sludge is ozone-treated, viscous substance on the surface of sludge particles can be separated with a comparatively small amount of ozone, with sludge concentration enhanced. At Meidensha, an experimental plant was set up for the ozone treatment of sludge in a sludge intensive treatment plant of a metropolis, with a verification experiment carried out for a sludge concentration improving system by ozone. As a result of comparison of the treatment performance between an assessment system for performing ozone treatment and a reference system for not performing, the average value of the sludge concentration of a gravity concentration tank was 1.9% of the reference system against 1.7% of the assessment system in a continuous treatment experiment in the summer, while the solid collection ratio was 65.8% of the reference system against 95.5% of the assessment system, enabling a superior improving effect to be obtained. (NEDO)

Gravitational sedimentation of flocculated waste activated sludge.

Science.gov (United States)

Chu, C P; Lee, D J; Tay, J H

2003-01-01

The sedimentation characteristics of flocculated wastewater sludge have not been satisfactorily explored using the non-destructive techniques, partially owing to the rather low solid content (ca. 1-2%) commonly noted in the biological sediments. This paper investigated, for the first time, the spatial-temporal gravitational settling characteristics of original and polyelectrolyte flocculated waste activated sludge using Computerized Axial Tomography Scanner. The waste activated sludge possessed a distinct settling characteristic from the kaolin slurries. The waste activated sludges settled more slowly and reached a lower solid fraction in the final sediment than the latter. Flocculation markedly enhanced the settleability of both sludges. Although the maximum achievable solid contents for the kaolin slurries were reduced, flocculation had little effects on the activated sludge. The purely plastic rheological model by Buscall and White (J Chem Soc Faraday Trans 1(83) (1987) 873) interpreted the consolidating sediment data, while the purely elastic model by Tiller and Leu (J. Chin. Inst. Chem. Eng. 11 (1980) 61) described the final equilibrated sediment. Flocculation produced lower yield stress during transient settling, thereby resulting in the more easily consolidated sludge than the original sample. Meanwhile, the flocculated activated sludge was stiffer in the final sediment than in the original sample. The data reported herein are valuable to the theories development for clarifier design and operation.

Siloxane removal and sludge disintegration using thermo-alkaline treatments with air stripping prior to anaerobic sludge digestion

International Nuclear Information System (INIS)

Oshita, Kazuyuki; Fujime, Motochika; Takaoka, Masaki; Fujimori, Takashi; Appels, Lise; Dewil, Raf

2015-01-01

Highlights: • Siloxanes hamper the energy-use of anaerobic digestion biogas. • D5 siloxane was considered as target compound in this study. • The treatment removed 80% of D5 in sewage sludge at 55 °C and 135 g-NaOH kg −1 -VTS. • D5 removal and the disintegration of VSS in the sludge were correlated. • At the optimal conditions, the costs of anaerobic digestion were notably diminished. - Abstract: A thermo-alkaline treatment with air stripping was applied before anaerobic sludge digestion for both siloxane removal and sludge disintegration. The treatment was expected to increase the amount of biogas produced and to reduce the amount of siloxane in the gas. Adding sodium hydroxide (NaOH) to the sludge improved the removal of siloxane from the sludge, with approximately 90% of the siloxane removed to the gas phase using a thermo-alkaline treatment. Over 80% of decamethylcyclopentasiloxane (D5) could be removed under the following conditions: 55 °C treatment temperature, 135 g-NaOH kg −1 volatile total solids (VTS), and 0.5 L min −1 air-stripping rate. The disintegration ratio of volatile suspended solids (VSS) in the sludge was correlated with the D5 removal ratio. Because most of the siloxane was adsorbed to, or was contained in the VSS, the siloxane removal ratio increased with VSS disintegration. Finally, the energy consumption and operational costs of this system were evaluated for several scenarios. Thermo-alkaline treatment at the indicated operational conditions had the lowest operating costs for a 400 m 3 day −1 anaerobic sludge digestion system

Gravity settling of Hanford single-shell tank sludges

International Nuclear Information System (INIS)

Brooks, K.P.; Rector, D.R.; Smith, P.A.

1999-01-01

The US Department of Energy plans to use gravity settling in million-gallon storage tanks while pretreating sludge on the Hanford site. To be considered viable in these large tanks, the supernatant must become clear, and the sludge must be concentrated in an acceptable time. These separations must occur over the wide range of conditions associated with sludge pretreatment. In the work reported here, gravity settling was studied with liter quantities of actual single-shell tank sludge from hanford Tank 241-C-107. Because of limited sludge availability, an approach was developed using the results of these liter-scale tests to predict full-scale operation. Samples were centrifuged at various g-forces to simulate compaction with higher layers of sludge. A semi-empirical settling model was then developed incorporating both the liter-scale settling data and the centrifuge compression results to describe the sludge behavior in a million-gallon tank. The settling model predicted that the compacted sludge solids would exceed 20 wt% in less than 30 days of settling in a 10-m-tall tank for all pretreatment steps

Assessing the potential of brachiaria decumbens as remediation agent for soil contaminated wit oil sludge

International Nuclear Information System (INIS)

Latiffah Norddin; Ahmad Nazrul Abd Wahid; Hazlina Abdullah; Abdul Razak Ruslan

2005-01-01

Bioremediation is a method of treatment of soil or water contaminated with toxic materials, involving the use of living organisms. Oil or petroleum sludge is a waste product of the petroleum refining industry, and is now accumulating at a fast rate at petroleum refinery sites in the country. Common components of oil sludge are mud and sand, containing toxic materials from hydrocarbons, heavy metals and radioactive elements from the seabed. In the present study, the oil sludge samples were obtained from barrels of the materials stored at the Radioactive Waste Treatment Centre, MINT. The samples were analysed of their compounds, elemental and radioactive contents. Trials on microbial degradation of the sludge materials were ongoing. This paper discusses the potential of a grass to remediate soils contaminated with petroleum sludge. Remediation of soils contaminated with organic compounds and heavy metals using plants, including grasses, including Vetiver, Lolium and Agrostis have been carried out in many countries. A greenhouse pot trial was conducted to assess the suitability of the pasture grass Brachiaria decumbens Stapf. and its mutant Brachiaria decumbens KLUANG Comel as a remediation agent for oil sludge contaminated soil. Samples of grasses and soils before planting, during growth stage and at end of experiment were analysed for the different toxicity. Although the grasses were promoted for use in pasture, and KLUANG Comel has good potential as an ornamental plant, too, their other potentials, including as phytoremediation agents need to be explored. (Author)

Factors Involved in Sludge Granulation under Anaerobic Conditions

Directory of Open Access Journals (Sweden)

Jalal Shayegan

2011-03-01

Full Text Available This paper investigates the effects of factors involved in sludge anaerobic granulation. Granulated sludge formation is the main parameter contributing to the success of UASB reactors. Anaerobic granulation leads to reduced reactor size, space requirement, and investment costs. Operation costs are also greatly reduced due to lack of aeration. An important parameter affecting process performance is the size of sludge granules; the factors involved in granule size will be investigated. Some of the important parameters of anaerobic sludge granulation are: existence of growth cores as inert particles or granulated sludge, process operational conditions (Sludge Loading Rate and Organic Loading Rate, Loading rate increase and …, and environment conditions (nutrients, temperature, pH, combination and ….

Ceramsite preparation from sea sludge with sewage sludge biochar and its environmental risk assessment

Science.gov (United States)

Li, Jie; Yu, Guangwei; Pan, Lanjia; Li, Chunxing; Xie, Shengyu; Wang, Gang; Wang, Yin

2018-02-01

Ceramsite were produced from sea sludge (SS) by adding different percentage of sewage sludge biochar (SSB). The characteristics of ceramsite including micrograph and elementary composition were analyzed. In addition, the heavy metals (HMs) fractions, leaching behaviour and potential environmental risk were also investigated. The microstructure of the ceramsite was slit pores and the main elements of the ceramsite were Si, Al and O. The residual fraction (F4) of Cu, Cr and Cd in ceramsite with 100% SS (SS100) reached the maximum (100%, 99% and 100%, respectively), while F4 of Zn and Ni in ceramsite with 80% SS and 20% SSB (SS80) reached the top value of 99.5% and 98%. Moreover, the HMs of feedstock can be immobilized after sintering as ceramsite and the leached amounts of HMs in all ceramsite were much lower than that stated by GB 5085.3-2007. Furthermore, ceramsite preparation from sea sludge with sewage sludge biochar will not bring HMs contamination and potential ecological risk.

Seawater-based wastewater accelerates development of aerobic granular sludge: A laboratory proof-of-concept.

Science.gov (United States)

Li, Xiling; Luo, Jinghai; Guo, Gang; Mackey, Hamish R; Hao, Tianwei; Chen, Guanghao

2017-05-15

This study aimed to develop an aerobic granular sludge process for the efficient treatment of highly saline wastewater and understand the granulation process in a seawater-based multi-ion matrix. Five identical sequencing batch airlift reactors (SBARs) are used to treat synthetic saline sewage with different proportions of real seawater (0%-100%). The results confirm that aerobic granular sludge can be successfully developed with various proportions of seawater up to 100% and show that seawater not only significantly accelerates granulation but also generates stronger granular structures than does freshwater. The increased presence of gel-forming alginate-like exopolysaccharides in the granules explains why a greater proportion of seawater leads to higher density and improves the cohesive strength of the granules. SEM-EDX analysis further revealed substantial presence of both Ca 2+ and Mg 2+ phosphate in the granule core as well as in the outer layers providing extra bridging forces in addition to alginate-like exopolysaccharides for accelerating the granule formation and maintaining the structure. It is hoped that this work could explore another approach for saline sewage treatment and bring some clues for the mystery of granulation mechanism. Copyright © 2017 Elsevier Ltd. All rights reserved.

Multi-scale individual-based model of microbial and bioconversion dynamics in aerobic granular sludge.

Science.gov (United States)

Xavier, Joao B; De Kreuk, Merle K; Picioreanu, Cristian; Van Loosdrecht, Mark C M

2007-09-15

Aerobic granular sludge is a novel compact biological wastewater treatment technology for integrated removal of COD (chemical oxygen demand), nitrogen, and phosphate charges. We present here a multiscale model of aerobic granular sludge sequencing batch reactors (GSBR) describing the complex dynamics of populations and nutrient removal. The macro scale describes bulk concentrations and effluent composition in six solutes (oxygen, acetate, ammonium, nitrite, nitrate, and phosphate). A finer scale, the scale of one granule (1.1 mm of diameter), describes the two-dimensional spatial arrangement of four bacterial groups--heterotrophs, ammonium oxidizers, nitrite oxidizers, and phosphate accumulating organisms (PAO)--using individual based modeling (IbM) with species-specific kinetic models. The model for PAO includes three internal storage compounds: polyhydroxyalkanoates (PHA), poly phosphate, and glycogen. Simulations of long-term reactor operation show how the microbial population and activity depends on the operating conditions. Short-term dynamics of solute bulk concentrations are also generated with results comparable to experimental data from lab scale reactors. Our results suggest that N-removal in GSBR occurs mostly via alternating nitrification/denitrification rather than simultaneous nitrification/denitrification, supporting an alternative strategy to improve N-removal in this promising wastewater treatment process.

PENERAPAN ELEKTROOSMOSIS UNTUK PENGERINGAN SLUDGE DARI PENGOLAHAN LIMBAH CAIR

Directory of Open Access Journals (Sweden)

Darmawan Darmawan

2013-11-01

Full Text Available APPLICATION OF ELECTROOSMOSIS FOR DEWATERING OF SLUDGE FROM WASTE WATER TREATMENT. Wastewater treatment produces semi-solid residue (sludge that must be handled carefully during dumping and discharge to avoid polluting the environment. A low cost and easy treatment of dewatering is needed. This research aimed to apply electroosmosis technique for dewatering sludge in order to seek for parameters that can efficiently reduce water content of sludge, including range of voltage, type of electrodes, and distance between electrodes; and to determine the effect of electroosmosis processes on changes of chemical characteristics of sludge. The results showed that: (1 electroosmosis dewatering occurred on the sludge taken from waste water treatment of landfill but not on sludge from water purification plant (PDAM, (2 direct current voltage of 30 volts was the optimum voltage, (3 copper rod cathode provided electroosmosis process as good as stainless steel cathode and both were better than the woven stainless steel cathode, (4 the dewatering time to reduce 1200% (w/w water content to about 400% was about 40 hours for sludge of 2500 cm3 in volume (laboratory bench scale, (5 the anode need to reinserted gradually approaching the cathode due to current lost when the water content at the anode point reached 400% and sludge at the point shrink, and (6 some chemical elements in the sludge decreased significantly after treatment. Pengolahan limbah cair menghasilkan residu berupa bahan semi padat yang dikenal sebagai sludge. Sludge tersebut juga perlu dikelola penyimpanan dan pembuangannya agar tidak mencemari lingkungan. Salah satu pengelolaan sludge yang perlu dilakukan adalah pengeringan (dewatering. Salahsatu teknik dewatering yang mungkin diterapkan ialah teknik elektroosmosis, yaitu teknik yang memanfaatkan adanya pergerakan air pada media poros di dalam medan istrik searah. Penelitian ini bertujuan untuk mencari parameter sistem dewatering secara

Changes on sewage sludge stability after greenhouse drying

Science.gov (United States)

Soriano-Disla, J. M.; Houot, S.; Imhoff, M.; Valentin, N.; Gómez, I.; Navarro-Pedreño, J.

2009-04-01

The progressive implementation of the Urban Waste Water Treatment Directive 91/271/EEC in all the European member states is increasing the quantities of sewage sludge requiring disposal. Sludge application onto cultivated soils as organic fertilizers allows the recycling of nutrients. The application of only dehydrated sludges has generated many problems including unpleasant odours and difficult management (regarding transport and application) related to their high water content. One way to overcome these problems, in a cheap and clean way, is the drying of sludges using the energy of the sun under greenhouse conditions. This drying may affect sludge chemical characteristics including organic matter stability and nitrogen availability, parameters which have to be controlled for the proper management of dry sludge application onto soils. For this reason, the main aim of this work was to study the impact of greenhouse drying of different sewage sludges on their organic matter stability and nitrogen availability, assessed by biochemical fractionation and mineralization assays. Three sewage sludges were sampled before (dehydrated sludges) and after greenhouse drying (dried sludges). The analyses consisted of: humidity, organic matter, mineral and organic N contents, N and C mineralization during 91-day laboratory incubations in controlled conditions, and biochemical fractionation using the Van Soest procedure. Greenhouse drying decreased the water content from 70-80% to 10% and also the odours, both of which will improve the management of the final product from the perspective of application and transport. We also found that drying reduced the organic matter content of the sludges but not the biodegradability of the remaining carbon. Organic N mineralization occurred during greenhouse drying, explaining why mineral N content tended to increase and the potential mineralization of organic nitrogen decreased after greenhouse drying. The biochemical stability did not

Effects of carbonization and solvent-extraction on change in fuel characteristics of sewage sludge.

Science.gov (United States)

Park, Sang-Woo; Jang, Cheol-Hyeon

2011-09-01

Urban sewage sludge was carbonized at 300-500°C for 1h, and combustible components were extracted through the solvent-extraction process. N-methyl-2-pyrrolidinone (NMP) was used as the solvent for extraction, and the extraction temperature was fixed at 360°C. The atomic ratios of the solvent-extracted sludge of CS300 (ECS300) were shown to be 1.04 for H/C and 0.11 for O/C, which represented the characteristics of its coal band. Thus, its coal band was similar to that of a high-rank fuel such as bituminous coal. FT-IR analysis showed that the absorbance band of ECS300 was considerably different from that of dried sludge (RS) or the carbonized sludge at 300°C (CS300) but similar to that of coal, although the ash content absorbance band of 800-1200 cm(-1) was of very low intensity. The combustion profile showed that combustion of ESC300 occurred at a temperature higher than the ignition temperature (T(i)) or maximum weight loss rate (DTG(max)) of coal. Copyright © 2011 Elsevier Ltd. All rights reserved.

Sewage sludge and how to sell it

Energy Technology Data Exchange (ETDEWEB)

Knapp, I M

1977-10-01

Largo, Florida dries its sludge and sells it as fertilizer for $80 to $169/T. The sludge processing plant capable of turning common sludge into a dry, pelletized soil conditioner was only slightly more expensive than the previously proposed concrete drying beds which would have required disposal of the dried residue. The city's experience in setting up the plant and marketing the finished product is discussed. The true advantage of selling heat-dried sludge is that residents of the surrounding area, knowing the value of the product to their lawns and shrubs, will provide the transportation for the product and the physical labor to spread it over an area wider than most municipalities could afford to own or operate. The current production cost of $140/T is high, but the addition of a sludge prethickener-conditioner process and expected future economies of scale as the volume of sludge treated increases should lower per ton costs.

Addition of biochar to sewage sludge decreases freely dissolved PAHs content and toxicity of sewage sludge-amended soil.

Science.gov (United States)

Stefaniuk, Magdalena; Oleszczuk, Patryk

2016-11-01

Due to an increased content of polycyclic aromatic hydrocarbons (PAHs) frequently found in sewage sludges, it is necessary to find solutions that will reduce the environmental hazard associated with their presence. The aim of this study was to determine changes of total and freely dissolved concentration of PAHs in sewage sludge-biochar-amended soil. Two different sewage sludges and biochars with varying properties were tested. Biochars (BC) were produced from biogas residues at 400 °C or 600 °C and from willow at 600 °C. The freely dissolved PAH concentration was determined by means of passive sampling using polyoxymethylene (POM). Total and freely dissolved PAH concentration was monitored at the beginning of the experiment and after 90 days of aging of the sewage sludge with the biochar and soil. Apart from chemical evaluation, the effect of biochar addition on the toxicity of the tested materials on bacteria - Vibrio fischeri (Microtox ® ), plants - Lepidium sativum (Phytotestkit F, Phytotoxkit F), and Collembola - Folsomia candida (Collembolan test) was evaluated. The addition of biochar to the sewage sludges decreased the content of C free PAHs. A reduction from 11 to 43% of sewage sludge toxicity or positive effects on plants expressed by root growth stimulation from 6 to 25% to the control was also found. The range of reduction of C free PAHs and toxicity was dependent on the type of biochar. After 90 days of incubation of the biochars with the sewage sludge in the soil, C free PAHs and toxicity were found to further decrease compared to the soil with sewage sludge alone. The obtained results show that the addition of biochar to sewage sludges may significantly reduce the risk associated with their environmental use both in terms of PAH content and toxicity of the materials tested. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of ultrasonic disintegration on sludge microbial activity and dewaterability

International Nuclear Information System (INIS)

Li Huan; Jin Yiying; Mahar, Rasool Bux; Wang Zhiyu; Nie Yongfeng

2009-01-01

Ultrasonic treatment can disintegrate sludge, enhance microbial activity and improve sludge dewaterability at different energy inputs. To find their relationship, the three phenomena during ultrasonic treatment were investigated synchronously, and an experimental model was established to describe the process of ultrasonic sludge disintegration. Analysis results showed that the changes of sludge microbial activity and dewaterability were dependent on sludge disintegration degree during ultrasonic treatment. When sludge disintegration degree was lower than 20%, sludge flocs were disintegrated into micro-floc aggregates and the microbial activity increased over 20%. When sludge disintegration degree was over 40%, most cells were destroyed at different degree, and sludge activity decreased drastically. Only when sludge disintegration degree was 2-5%, sludge dewaterability was improved with the conditioning of FeCl 3 . It was also found that the sonication with low density and long duration was more efficient than sonication with high density and short duration at the same energy input for sludge disintegration, and a transmutative power function model can be used to describe the process of ultrasonic disintegration

Effects of ultrasonic disintegration on sludge microbial activity and dewaterability.

Science.gov (United States)

Huan, Li; Yiying, Jin; Mahar, Rasool Bux; Zhiyu, Wang; Yongfeng, Nie

2009-01-30

Ultrasonic treatment can disintegrate sludge, enhance microbial activity and improve sludge dewaterability at different energy inputs. To find their relationship, the three phenomena during ultrasonic treatment were investigated synchronously, and an experimental model was established to describe the process of ultrasonic sludge disintegration. Analysis results showed that the changes of sludge microbial activity and dewaterability were dependent on sludge disintegration degree during ultrasonic treatment. When sludge disintegration degree was lower than 20%, sludge flocs were disintegrated into micro-floc aggregates and the microbial activity increased over 20%. When sludge disintegration degree was over 40%, most cells were destroyed at different degree, and sludge activity decreased drastically. Only when sludge disintegration degree was 2-5%, sludge dewaterability was improved with the conditioning of FeCl(3). It was also found that the sonication with low density and long duration was more efficient than sonication with high density and short duration at the same energy input for sludge disintegration, and a transmutative power function model can be used to describe the process of ultrasonic disintegration.

The Noell Conversion Process - a gasification process for the pollutant-free disposal of sewage sludge and the recovery of energy and materials

Energy Technology Data Exchange (ETDEWEB)

Jaeger, M. [Preussag Noell GmbH, Wuerzburg (Germany); Mayer, M. [Noell-KRC Energie- und Umwelttechnik GmbH, Wuerzburg (Germany)

2000-07-01

The Noell Conversion Process was developed to guarantee the safe disposal of sewage sludge and other waste materials by means of thermal treatment, even with every strict emission standards. The center piece of this process is a pressurised entrained flow gasifier. The reacting conditions in this gasifier does not only suppresses the formation of dioxins and furans, but also completely destroys and dioxins and furans contained in the waste materials. Another advantage of the Noell Conversion Process referring the thermal treatment of sewage sludge is the recovery of marketable substances such as synthesis gas, sulphur and vitrified slag. To demonstrate this advanced technology in the field of sewage sludge treatment, Noell-KRC has built a pilot plant in Freiberg/Germany. This plant was designed for a throughput of 0.5 Mg/h (dry base) of sewage sludge. During the operation of the plant from 1996 until 1998, it was possible to demonstrate that there are no problems with emissions of heavy metals like Mercury or organic components like Dioxins and Furans. The H2 rich gas produced in the process can be utilised as a power source. The vitrified slag produced in the process is of a quality suitable for use as a construction material with a wide range of applications. (Author)

Recycling of oil sludge through of the incorporation in bricks; Reciclagem de borra oleosa atraves de incorporacao em blocos ceramicos de vedacao